Bamco v Contek - [2019] VCC 327

IN THE COUNTY COURT OF VICTORIA

AT MELBOURNE

COMMERCIAL DIVISION
GENERAL LIST

Revised
Not Restricted
Suitable for Publication

Case No. CI-17-00268

BAMCO GROVE PTY LTD	First Plaintiff
and
B22 PTY LTD	Second Plaintiff
v
CONTEK CONSTRUCTIONS PTY LTD	First Defendant
and
YARRA RANGES SHIRE COUNCIL	Second Defendant

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JUDGE:	HER HONOUR JUDGE MARKS
WHERE HELD:	Melbourne
DATE OF HEARING:	13-16, 19-21, 26-29 November 2018, 3 December 2018; further written submissions received from the parties on 4 and 5 December 2018
DATE OF JUDGMENT:	22 March 2019
CASE MAY BE CITED AS:	Bamco v Contek
MEDIUM NEUTRAL CITATION:	[2019] VCC 327

REASONS FOR JUDGMENT
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TORTS – NEGLIGENCE – duty of care – scope and existence of duty – whether failure to comply with contract incorporating arboricultural impact report recommendations when constructing boardwalk caused tree to fall – causation not established.

EXPERT EVIDENCE – overarching obligations – duties of experts to court – Expert Code of Conduct – requirement of expert witness to be independent – expert arborist – ongoing conferences between expert and solicitor for party relying on expert witness evidence – significant changes to draft report of expert subsequent to conferences – references in solicitor's diary note to 'we concluded' – not satisfied expert an independent expert – Hudspeth v Scholastic Cleaning And Consultancy Services Pty Ltd & Ors (No 8) [2014] VSC 567 – Secretary to the Department of Business and Innovation v Murdesk Investments Pty Ltd [2011] VSC 581 and Secretary to the Department of Business and Innovation v Murdesk Investments Pty Ltd [2012] VSC 319.

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APPEARANCES:	Counsel	Solicitors
For the first and second plaintiffs	Ms K Foley	Lander & Rogers
For the first defendant	Mr PJ Hayes QC, with Dr M Barrett	Terrill & Holmes Pty Ltd

Contents

INTRODUCTION

BACKGROUND

AIA Report
Environmental Management Plan
Contract
Construction
Witnesses

DUTY OF CARE

CAUSATION
BREACHES ALLEGED

A - Not minimising root disturbance in tree 25’s TPZ
B - Cutting roots in tree 25’s SRZ
C - Not hand digging pier holes in tree 25’s SRZ and not repositioning the piers if structural roots were found in the SRZ
D - Not putting geotextile fabric, a layer of mulch and strapped boards where there would be foot traffic/equipment in tree 25’s TPZ
E - Putting rock ballast or beaching in tree 25’s TPZ
F - Not having an arborist onsite to supervise the excavation works

DR NICOLLE’S EVIDENCE

Communication with solicitors
Changes between Draft 1 and Draft 2
Reasons for changes
Diary notes
Nicolle’s independence

MR HARTLEY’S EVIDENCE

CONCLUSION

HER HONOUR:

INTRODUCTION

It was a dark and windy night. On 2 August 2014, around 1am, an approximately 42 metre tall Mountain Ash tree fell in the Dandenong Ranges in Victoria. The tree had been on the eastern side of Monbulk Road in Belgrave. It fell in a westerly direction over the road, landing across the Micawber tavern, which was about 29 metres away. The tavern – a family run local pub and eatery – had extensive damage. It was closed for two and a half months for repairs.
Some eighteen months earlier, Contek Constructions Pty Ltd had constructed a boardwalk which ran next to Monbulk Road – and near the tree.
Bamco Grove Pty Ltd, the first plaintiff, is the owner of the tavern. B22 Pty Ltd, the second plaintiff, leased it from Bamco and ran the tavern business from it. The plaintiffs claim damages for loss they suffered because the tree collapsed on to the tavern. They say that a cause of the tree falling was Contek’s negligence when it constructed the boardwalk.
The plaintiffs initially also sued the Yarra Ranges Shire Council, which had engaged Contek to construct the boardwalk. However, by the time of trial, the plaintiffs’ case against the council had been resolved by consent.
For the reasons that follow, I am not satisfied that Contek’s negligence was a cause of the tree falling.
I will therefore dismiss the plaintiffs’ claim.

BACKGROUND

AIA Report

In 2010, the Yarra Ranges Shire Council decided to build a footpath and boardwalk along Monbulk Road in Belgrave. It commissioned Mr David Galwey of Tree Dimensions to provide an arboricultural impacts assessment for trees nearby. He produced that assessment (the AIA report) in June 2011.
The report set out its objectives at [1.1]:
Identify and assess the trees, providing their location, species, dimensions, age, health and structural condition, and their suitability for retention;
Identify trees that will need to be removed for the works;
Calculate the size of the area that requires protection (TPZ) around trees being retained;
Identify potential impacts of the works on trees being retained;
Specify protection measures for trees being retained near works.
A footpath was proposed for the area south of Glen Harrow Heights Road and a boardwalk for the area to the north of the road. The AIA report states:
A new footpath is proposed along the east side of Monbulk Road, linking existing pedestrian access out of the Belgrave township from Cole Avenue with the Bleakley Track walking trail. South of Glen Harrow Heights Road the footpath is to be constructed on the existing grade and should have no significant impacts on trees. In this area there are isolated trees but no other significant vegetation. North of Glen Harrow Heights Road the terrain becomes steeper and there is dense vegetation. The path will be constructed as a boardwalk in this section. A route has been selected to minimise impacts on vegetation.
…
The proposed walkway will be to the east of Monbulk Road, north of Glen Harrow Heights Road to the end of the existing walking trail (Bleakley Track). Dandenong Ranges National Park is immediately to the north.
The AIA report described the need to protect tree roots, specifying this by reference to the tree protection zones (TPZ) and structural root zones (SRZ) of the trees.
The AIA report noted at [4.1] that:
Trees require space not only for their canopies, but also for their roots. Failure to protect roots during development usually leads to future problems – stressed trees or trees prone to wind-throw.
Most tree roots will usually be found in the top 600mm of soil… Radiating outwards from the base of the trunk are several large woody roots. These structural roots anchor the tree in the ground. Cutting or affecting these roots is likely to undermine the stability of the tree. The spread of a tree’s structural roots, herein termed its Structural Root Zone (SRZ) is generally proportional to the diameter of its trunk…
Beyond this zone extends the network of woody transport roots and fine absorption roots, which absorb and transport water and nutrients. Most of these roots are found in the top 150mm of soil…. Trees can lose a portion of their absorption roots without being significantly affected in the long term. Different species tolerate different amounts of root loss, with most healthy trees able to tolerate losing up to a third of their absorption roots….
…
The Tree Protection Zone (TPZ) radius … indicates the zone that should be protected from development on all sides if a tree is to be retained, and should protect all structural roots and sufficient absorbing roots for the tree to remain viable. …
Trees can be affected by development in several ways. Direct damage to roots through trenching and site cuts can remove absorption roots and sever structural roots. Root activity can be inhibited by various activities: soil compaction in the root zone, sealing the surface and adding fill over roots. These activities limit the amount of oxygen and moisture that may reach the roots, and without which roots cannot function. This will lead to drought stress and even death, and may take several years to become evident in the crown.
At [4.3] it states:
The path north of Glen Harrow Heights Road begins at grade, where it passes tree #1. It then becomes a raised boardwalk supported by piers. The boardwalk has been designed so it is above grade for most of its length. Locating the boardwalk relatively close to several trees has minimised the need for any cutting into the slope – there are very few areas requiring a slight cut. However this will not affect more than 10% of any Tree Protection Zone. It has avoided any cutting within Structural Root Zones, but may require the locating of some supporting piers within Structural Root Zones. Done with care, this will not adversely affect the trees.
The AIA report assesses 27 trees in the relevant area, describing each tree and giving it a number. It recommends the removal of six trees, not including the tree in question in this case (which it described as tree #25.)
It records that the boardwalk is within the TPZs of 15 trees, and that it would pass within the SRZs of four of them, including tree 25.
It records that the TPZ of tree 25 was 14.9 metres, and its SRZ was 3.6 metres.
At [4.3.2] it sets out:
The boardwalk is within the TPZs of the remaining 15 trees. …
The boardwalk passes within the SRZs of four of the trees: #14, 15, 25 & 26. If piers supporting the boardwalk are outside their SRZs, but within their TPZs, standard protection measures can be applied and the trees would not be adversely affected, as less than 10% of their TPZs would be affected by the piers and structural roots would not be damaged. If piers are required within their SRZs, holes should be dug by hand to 600mm depth to determine if major woody (structural) roots are present. If such roots are encountered, there must be scope to reposition the piers. If no such roots are found, pier holes can be completed using mechanical means.
Importantly – in relation to the issues in this case – the AIA report at [5.2] sets out four recommendations in relation to how the trees were to be looked after, and at [5.3] sets out ten tree protection measures. The plaintiffs allege that several of these recommendations and tree protection measures were not complied with by Contek. These are discussed below, under the heading ‘Breaches Alleged’.

Environmental Management Plan

An environmental management plan was also prepared for the boardwalk project. It included the AIA report as an annexure. The environmental management plan included reference to an ‘environmental induction’ to take place with the works superintendent and the ‘project arborist’:
1.1 Pre- Construction Requirements:
An Environmental Induction is to occur with the works superintendent and project arborist to identify the required Tree Protection measures as outlined below and the protection measures that are included in the associated arborist report. This induction should confirm a supervision schedule with the project arborist and also identify the trees approved to be removed with tags, spray paint or similar.
1.2 Tree Retention and Removal
In accordance with the arborist report dated 11 June 2011 non-native trees have been approved for removal. …
All other trees throughout the subject area are to be retained. However, there is a risk during construction that excavation works will encroach beneath the canopy of native trees, resulting in impacts to tree root zones which can contribute to tree decline over time. Significant tree protection measures are required during the construction of the boardwalk as outlined in the attached arborist report. Other tree protection measures have been outlined below and on the attached maps.
Contract

The council called for tenders for construction of the boardwalk. Contek won the tender, and on 25 November 2012, the council entered into a contract with Contek for the construction of the boardwalk.
The AIA report was annexed to the contract. (Somewhat confusingly, given the existence of a separate environmental plan which annexed the AIA report, in the contract the AIA report was described as the environmental management plan. Nothing turns on this.)
Contek was required to undertake its works under the contract in accordance Australian Standard 4970-2009.

Construction

On 29 January 2013, Contek, the council and Tree Dimensions had a site induction meeting.
On 4 February 2013, the site was cleared to conduct the works.
A site inspection occurred on 5 February 2013. Mr Theo Glatthor and Mr Matt Sauvarin – consulting arborists at Tree Dimensions – attended.
In a letter from Tree Dimensions sent on 7 September 2015, Tree Dimensions notes that it inspected the works twice to assess any impacts. It says the following about the 5 February inspection:
The first site inspection was done on 5 February 2013 by Theo Glatthor and Matt Sauvarin, consulting arborists at Tree Dimensions. They attended a site meeting. Photographs taken during the inspection are included below. At this stage tree removals were being done and the area was being mulched. No damage to trees was observed.
On 19 February 2013, Sauvarin carried out Tree Dimensions’ second inspection of the site. According to Tree Dimensions’ letter of 7 September 2015, he observed no damage to the trees:
Matt Sauvarin inspected the site on 19 February 2013 to photograph the progress of works. We don’t have a record of a request for this inspection so Matt may have done it as he passed by the site. No damage to trees was observed. Photographs taken during the inspection are included below.
One of the photographs taken on 19 February and included with the letter is described as ‘Construction around tree ^#25’. It shows the trunk of tree 25 and the boardwalk in the process of being constructed nearby. It is relied on by the plaintiffs and referenced by the expert arborists who gave evidence in this case.
Tree Dimensions sent an invoice on 28 June 2013, to the council for 2 hours work, over January/February 2013, claiming $240 for:
Arboricultural consultancy services Monbulk Road, Belgrave: boardwalk project
Supervision of works near trees, onsite meetings and advice January/February 2013
There is some dispute about just how windy it was near the tree in the couple of days leading up to the tree falling. However, there is no dispute that the conditions on 30 July 2014 and 1 August 2014 were windy, and that the wind was a cause of the tree falling.
Early in the morning of 2 August 2014, tree 25 fell.
Ms Kristina Beatty-Johnson (the manager and director of the tavern) gave evidence that she was at home when she received a call about it having fallen after 1am. She said that the pub had shut around 11:45pm.
She arrived at the tavern around 4am (her husband having gone there first) and observed:
a very large tree that was across the road, across our driveway lying over our - well, lying on top of what was once our office and back kitchen area, reaching up to the cottage.
Asked if she recalled it was a windy night, she said:
I don’t believe there was gale force winds where we were, it’s not – we live up the mountains and I’m – I have to be aware of those things. That’s why when we got the phone call like if there’s gale force winds I would have rostered myself on. When we got the call that’s (indistinct) why my husband went in, it wasn’t – it was just a surprise, there’s a tree, you know we didn’t expect it to be such a tree. But at the point in time there was nothing – I mean I’ve certainly seen bigger things in the mountain and when you go and you drive in you have to move through debris, et cetera on the road that you know winds can come to. In saying that we do live up in the mountains and there are different areas that get hit by winds. You can drive around one corner and there can be a horrendous pocket of debris on the roads, and then you can drive around the next corner and it can be quite pristine and clear. So at the point in time we weren’t impacted by any storms or weather.
Cross-examined about whether she was not surprised to hear that experts said there were near gale force winds nearby, she said she was not in a position to comment and that there may have been or may not have been.
Mr Andrew McKernan gave evidence that he saw the tree the day after it fell – probably the next morning. He was asked by the publican to remove the tree so they could repair the hotel. He said he observed:
A large mountain ash tree had fallen cross the main road, across the car park driveway and fallen mainly through the office space. Some branches had gone into the actual main room of the hotel. The portion of the trunk across the highway had been cleared prior to us arriving, I’d say by emergency maintenance crews, they’d just cut the piece of trunk and pushed that out of the way but nothing had been cleared from the site apart from moving that piece of trunk.
Asked what work he then undertook, he answered:
So then we then got in some machinery to lift the heavy logs because they were embedded in the rubble of the building and they were very heavy from a handling point of view, so we craned out – actually excavated out what we needed to and put the head of the tree or the foliage through a wood chipper. We removed the logs from the area and put them up the other end of the car park.
He said he went across the road and looked. He could see exposed tree roots were damaged. He observed no decay in trunk structure or in the crown; he said he saw brown rot in the roots.
Six days after the tree fell, on 8 August 2014, there was a joint media release by the Minister for Justice the Hon Michael Keenan MP, and the Victorian Minister for Police and Emergency Services, the Hon Kim Wells MP. It announced disaster assistance for areas – including the Yarra Ranges – ‘following storms in late July’. It stated that:
Mr Wells said the July storms caused damage to public infrastructure across the affected local government areas and extensive clear-up operations were undertaken by the councils.
“This funding will help affected councils with the costs of repairing damaged essential public assets and undertaking clean-up operations,” Mr Wells said.
Mr Wells praised the efforts of local council and emergency services personnel in helping affected communities in the aftermath of the storm.
Two and a half months after the tree fell, on 16 October 2014, Mr Mark Delaney first inspected the site for the council. He inspected it a few more times in the next few days, in order to try to determine a likely reason for the tree’s failure. His conclusions are noted in the Yarra Ranges Shire Council tree inspection report of 23 October 2014. The report notes:
OBSERVATIONS:
At the time of initial inspection of the root plate on 16/10/14 at approximately 3:30 pm the stem had been cut back to within approximately 60 centimetres of the root plate at what would have been the original soil level. There was absolutely no decay visible in the exposed inner wood of the lower stem.
The upturned root plate was checked and almost every broken root exposed as a result of the failure was observed to be significantly decayed by a white rot. There was no structural strength left in the decayed roots. Only two relatively shallow roots on the east side of the stem were observed to be in reasonably healthy condition and would have been providing most of the trees tension root support. The tree has pivoted over from the point of decayed roots immediately on the west side of the stem between the stem and the boardwalk.
During grinding of the stump large structural roots were observed to have decayed into the very base of the stem but had not yet spread into the lower stem just above ground level. The stump grinder operator reported that large areas of the upturned stump offered virtually no resistance to the grinder due to the amount of decay.
The hole left by the upturned root plate was reported to have been quite moist and muddy when observed by Coordinator of Trees Paul Mechelen approximately one month after tree failure. It also appears the tree failed with a full canopy with a healthy appearance during wet and windy conditions. The tree was noted to be weighted across Monbulk road and towards the Micawber Tavern probably due to the light regime for a forest edge tree. The stem also leant to the west prior to failure.
An elevated board walk had been constructed within approximately 2 metres of the stem base. Based on on-site discussions with a representative of Com-Tek [sic] (builder of the boardwalk) on 16/10/2014 the boardwalk was completed around 18 months prior to the tree failing. The soil level on the west side of the tree was lowered to accommodate the boardwalk. Based on inspection of the root plate after the damaged sections of boardwalk had been removed it was evident some roots had been severed. Most roots severed would have been quite small however two large roots of approximately 17 centimetres and 20 centimetres had been severed/ broken. Some brown rot was observed in the end of one of the roots which appears to be natural degradation at the broken end. This root was very close to one of the support piles for the boardwalk. The other root did not appear decayed probably because it was suspended in the air under the boardwalk once the soil levels had been lowered.
CONCLUSIONS:
The tree was observed to have had major decay of virtually all of its structural support roots yet appeared to have exhibited a reasonably healthy canopy at the time of failure. The type of fungal decay observed was consistent with a white rot. Given that the tree failed during winter with a full and reasonably healthy canopy it is likely that most of the roots died and decayed over a relatively short period of time. Had the tree remained upright into the coming Summer months I would expect that the trees foliage would have browned off and likely followed by complete tree death. At the very least given the lack of healthy roots; major dieback and other signs of tree health stress would have been visible as the warmer months progressed.
Low requirements for moisture during Winter and therefore slow transpiration rates have allowed the tree to present as healthy despite the death and loss of most structural and feeder roots to decay. The full canopy also contributes to greater loading on the compromised root plate which was exacerbated by the trees lean and asymmetrical canopy distribution over Monbulk Road. Further to this the weather conditions at the time were wet and windy and the soil conditions around the tree base appeared to have been quite wet. Soils have reduced strength whilst saturated.
Some rock had been placed under the boardwalk presumably to reduce erosion of soil for water running immediately past the tree to the North side. This natural drainage line may have contributed to the wet soil around the tree. It is not clear whether any of the nearby civil works exacerbated the moisture levels around the tree as water must have run past the tree for many years. Wetter soils may be the reason that roots died and at some point conditions became very favourable for fungal decay. Two reasonably substantial tension roots on the east side were fairly healthy when they broke but these roots were at a shallow depth and spreading uphill from the tree. They are likely to have been in better aerated and shallower soils giving rise to the likelihood that other deeper roots particularly close to the stem died initially as a result of wetter soil, despite the obvious slope of the land.
Whilst the root severance which appears to have occurred as a result the board walk construction is far from ideal it does not appear this directly contributed to the trees failure. The point at which the root plate fractured was between the point of root severance and the stem. Had the tree failed as a result of the severance I would expect that the severed roots would have turned vertical with the rest of the root plate. As it was they stayed in position.
Degradation of one of the severed roots appeared to be a brown rot and is not consistent with the white rot which compromised the rest of the decayed structural roots. It is therefore unlikely that the decay which caused the failure originated from the severed roots. The white rot appears to have come up from the roots under the tree and into the extreme base of the stem rather than started in the stem and spread down into the roots.
In summary it appears the tree primarily failed as a result of the extremely decayed root plate which was not evident or visible until the root plate upturned and exposed the major roots.

The next day, on 24 October 2014, the tavern reopened.
On 6 May 2015 – more than two years after Contek built the boardwalk – Mr Daniel Sinclair of Contek sent Mr Lance Hamlett of the council an email attaching some documents including pile reports. His email mistakenly named the wrong external arborist as having been involved, Tree Logic rather than Tree Dimensions:
See attached for asbuilts and supporting information. Please note the project was supervised by an external arborist Tree Logic, all stump holes and excavations were inspected ensuring tree health wasn’t jeopardised.
On 7 September 2015, Tree Dimensions sent the council the letter previously referred to in relation to its two inspections of 5 and 19 February 2013. The letter included the following:
Apart from these inspections we were not asked to inspect the site during the works. We did not supervise digging of the pier holes.
Eighteen months after the tree fell, in March 2016, Dr Dean Nicolle, an expert arborist, was first retained by the solicitors for the plaintiffs to review documentation and provide his opinion on the cause of the tree’s collapse. He provided two draft reports, then a final report dated 19 August 2016 which was filed and relied on at trial, and a supplementary report dated 28 August 2018.
Mr Mark Hartley, an expert arborist, provided a report dated 28 May 2018, which was filed and relied on at trial by Contek.
Witnesses

Evidence for the plaintiffs was given by Mr Andrew McKernan, Ms Kristina Beatty-Johnston, Dr Dean Nicolle and Ms Kimberley Daley.
Evidence for the first defendant was given by Mr Daniel Sinclair, Mr Robert Davidson, Mr Mark Hartley, and Mr Gary Fettes.
The two witnesses actually involved in the construction of the boardwalk were Sinclair and Davidson.
Sinclair was the project manager for the construction works. He holds a Bachelor of Engineering. He started to work for Contek in late 2012 or early 2013. At that stage he was a graduate project manager, a qualified civil engineer and carpenter. It was his first professional job out of university and he was 26.
Davidson undertook excavation work including clearing the site and operating a backhoe.
I found them both to be honest and direct in giving their evidence. They made appropriate concessions when they did not recall matters. It was not surprising that in some instances they did not recall the detail of what had occurred during construction, given the time that had elapsed since.
In Sinclair’s email of 6 May 2015, he included a pile report which had additions referring to ‘sand/tree roots experience’ and ‘rock/tree roots experience’ at particular site locations. These additions were made to an original version of the pile log he had sent the council in February 2013. He was cross-examined about why he sent the council the amended pile log. It was suggested to him that when he sent the amended pile report – at a time after the tree had fallen – he was concerned the council would ask questions about why nothing had been included in the earlier report about these encounters with roots. Sinclair gave evidence that, after the tree fell, questions were asked about the construction works, and he went back and changed pile reports to include the references to encountering roots. He said he recalled experiencing tree roots in the middle of the works so he went back and looked at sectional reports and added that information to the pile report, in 2015, in order to give ‘as much information as I could at that date’.
I accept his evidence as to why he made the changes, and the process he carried out in doing so. It is noteworthy that both versions of the reports were sent to the council.

DUTY OF CARE

The existence of a duty of care owed by a building contractor to the owner of property damaged as a result of negligent building work is well established. In Bryan v Maloney (1995) 182 CLR 609 at 632, Brennan J (as his Honour then was) said:
The cases dealing with an architect’s or builder's liability in negligence for carelessly designing or constructing a building have been concerned to distinguish between two general categories of damage. The first category consists of physical damage to person or property for which a defendant is, and always has been, liable under the paradigm application of Donoghue v Stevenson; the second category consists of pure economic loss for which a defendant may be liable in negligence under principles that have been developed from Lord Atkin's original conception in that case, especially since Hedley Byrne and Co. Ltd. v. Heller and Partners Ltd. [citations omitted]
R P Balkin & J L R Davis, Law of Torts (4th ed, 2009) at [13.5] states:
… [in] cases where the plaintiff’s property has been damaged by a force external to that property and the plaintiff seeks to recover the cost of repairing or replacing it. In most such cases, it has been said, it is self-evident that the person responsible for the damage owes a duty of care to the owner of the property.
The plaintiffs alleged that Contek owed a duty of care to them to take reasonable care in undertaking construction of the boardwalk, the content of which required it to comply with the recommendations of the AIA report and/or AS 4970-2009.
Contek asserts that it owed the plaintiffs a duty to take reasonable care in its performance of the contract as varied, which incorporated the AIA report and AS 4970-2009.
I consider Contek’s duty to the plaintiffs was to take reasonable care in constructing the boardwalk, given the contractual requirement that it comply with the recommendations of the AIA report and AS 4970-2009.

CAUSATION

Section 51 of the Wrongs Act 1958 (Vic) provides:
(1) A determination that negligence caused particular harm comprises the following elements—
(a) that the negligence was a necessary condition of the occurrence of the harm (factual causation); and
(b) that it is appropriate for the scope of the negligent person's liability to extend to the harm so caused (scope of liability).
(2) In determining in an appropriate case, in accordance with established principles, whether negligence that cannot be established as a necessary condition of the occurrence of harm should be taken to establish factual causation, the court is to consider (amongst other relevant things) whether or not and why responsibility for the harm should be imposed on the negligent party.
(3) If it is relevant to the determination of factual causation to determine what the person who suffered harm (the injured person) would have done if the negligent person had not been negligent, the matter is to be determined subjectively in the light of all relevant circumstances.
(4) For the purpose of determining the scope of liability, the court is to consider (amongst other relevant things) whether or not and why responsibility for the harm should be imposed on the negligent party.
To determine that negligence caused particular harm it is necessary to show two things. First that the negligence factually caused the harm. Secondly, that it is appropriate for the scope of the negligent person's liability to extend to the harm so caused.
To prove factual causation, it is not necessary to show that Contek’s failures were the only factors contributing to the tree falling: See Dual Homes Pty Ltd v Moores Legal Pty Ltd (2016) 50 VR 129 at [198].
The plaintiffs bear the burden of establishing on the balance of probabilities that Contek was negligent and that its negligence caused the tree to fall. It is not sufficient for them to establish that if there were negligence that increased the risk of the tree falling: Shire of Wakool v Walters [2005] VSCA 216 at [43 – 52] (Nettle JA, with whom Buchanan JA and Hollingworth AJA agreed). This is particularly so when there are many other likely contributing factors.
The plaintiffs submit that the evidence establishes to the necessary standard that tree 25 would not have fallen when it did, but for the negligent site works undertaken by Contek. They say that whilst there were other contributing factors to the tree’s failure – such as certain characteristics of the tree itself, and natural forces applied to the tree – the tree would not have failed at the time it did, absent Contek’s failure to comply with the AIA report.
The plaintiffs are required to establish their case on the balance of probabilities.
As set out below, I am satisfied, on the balance of probabilities that Contek failed to comply with the AIA report in certain respects. However, I am not satisfied that any of those failures was a cause of the tree falling, or that all of them together were a cause of it falling.
Putting this another way, I am not satisfied that but for each such breach and its consequences the tree would not have fallen when it did in the way that it did.
I deal first below with my factual findings about the breaches alleged. I am satisfied that Contek did fail to comply with some aspects of the AIA report.
However, I am not satisfied any such failure was a cause of the tree falling. For the reasons discussed below, I prefer the evidence as to causation of Mr Hartley, the expert relied on by Contek, over that of Dr Nicolle, the expert relied on by the plaintiffs.
In short, Hartley was of the view that the reasons the tree fell did not include Contek’s actions in construction of the boardwalk.
Accordingly, I am not satisfied on the balance of probabilities that the plaintiffs have made out their case.

BREACHES ALLEGED

In the amended statement of claim at [18], the plaintiffs allege Contek breached its duty of care in nine ways while undertaking construction of the boardwalk. They allege Contek failed:
·     to dig holes within tree 25’s SRZ by hand;
·     to ensure that no roots were damaged or severed within tree 25’s SRZ;
·     to ensure that excavation within tree 25’s TPZ was approved in advance by a responsible authority;
·     to ensure that excavation within tree 25’s TPZ was supervised by an arborist;
·     to ensure that any roots falling outside tree 25’s SRZ, but within its TPZ, were cut cleanly with a saw;
·     to ensure that the soil within tree 25’s TPZ was protected from compaction;
·     to ensure tree protection fencing of high visibility parawebbing or similar was in place surrounding relevant trees including tree 25;
·     to ensure any damage to trees, including roots of a tree, is immediately reported; and
·     to properly or adequately ensure the TPZ is protected from compaction by using geotextile fabric, mulch/woodchip, and strapped boards.
By the time closing submissions were made, the plaintiffs’ case in relation to the alleged breaches of duty had altered. Contek did not oppose that alteration.
The breaches of duty finally alleged were that Contek failed to comply with the requirements of the AIA report in that it:
·Failed to minimise root disturbance in tree 25’s TPZ;
·Cut roots in tree 25’s SRZ;
·Failed to dig pier holes in tree 25’s SRZ by hand;
·Failed to reposition the piers if structural roots were found in the SRZ;
·Failed to protect the ground from compaction: including by failing to place geotextile fabric, a layer of mulch and strapped boards where there would be foot traffic or equipment in tree 25’s TPZ; and by putting rock ballast or beaching in tree 25’s TPZ;
·Failed to have a project arborist onsite to supervise the excavation works.
The breaches are alleged to be failures to comply with four recommendations set within [5.2] of the AIA report. The fourth of those provides that various protection measures are to be implemented during all site works. Ten tree protection measures are then listed at [5.3]. In other words, failure to comply with those tree protection measures amounts to a breach of that fourth recommendation. (For convenience in this judgment, I refer to each of the recommendations and tree protection measures by number in the order they appear in [5.2] and [5.3] of the AIA report, although they do not there have numbers set out next to them).
Contek denies the breaches. In the defence to the amended statement of claim at [18], it further asserts that any pier holes within the SRZ of a tree were dug by hand, and that it complied with all tree protection measures as required in the contract and/or as directed by the council’s on-site work supervisor.

A - Not minimising root disturbance in tree 25’s TPZ

The plaintiffs allege that Contek breached the AIA report by failing to minimise root disturbance in tree 25’s TPZ.
I am satisfied that this breach occurred.
Recommendation 2 of the AIA report states:
Trees being retained are to be protected during works. Roots must not be cut within their Structural Root Zones (SRZs). Root disturbance must be minimised within their Tree Protection Zones (TPZs).
Tree protection measure 5 states:
Root damage must be minimised within the trees’ TPZs. If major changes are required within TPZs, or if major roots within TPZs must be severed, the project arborist should be onsite to supervise the works.
Tree protection measure 6 states:
Where possible, tree protection measures are to comply with Australian Standard: Protection of Trees on Development Sites (AS 4970 – 2009)….
Tree protection measure 8 states:
No filling or excavation is to occur within Tree Protection Zones except as approved by the responsible authority. Any roots encountered when excavating must be cut cleanly with a saw.
The relevant Australian Standard 4970-2009 states at [4.5.4]:
Some approved works within the TPZ, such as regrading, installation of piers or landscaping may have the potential to damage roots.
….
Manual excavation should be carried out under the supervision of the project arborist to identify roots critical to tree stability. Relocation or redesign of works may be required.
Where the project arborist identifies roots to be pruned within or at the outer edge of the TPZ, they should be pruned with a final cut to undamaged wood. Pruning cuts should be made with sharp tools such as secateurs, pruners, handsaws or chainsaws … It is not acceptable for roots within the TPZ to be ‘pruned’ with machinery such as backhoes or excavators.
I am satisfied on the evidence that the main site cut (provided for in the original contract) was not within the TPZ of tree 25. However, there was a 7 March variation which involved an additional site cut. Carrying that out included what Davidson described as ‘minor excavation’, some of which was within the tree’s TPZ.
The plaintiffs submitted that an ‘extensive area of soil’ was excavated near tree 25. They said that this excavation failed to minimise root disturbance in the TPZ.
Davidson was a Contek employee who worked on the site as a backhoe operator. His main responsibility was to clear the site of vegetation so that Sinclair could then mark out the alignment of the site and create a ‘safe platform to …work on’.
Davidson’s evidence is that he did not undertake any major earthworks at the northern end of the boardwalk. He scraped off the topsoil of the site along the eastern edge of the batter/slope to prepare the site for the construction of the framework to support the boards.
Davidson gave evidence that the main site cut was in the central section. The main site cut and the additional excavation at the northern end near the tree were separate excavation works.
He was shown the ‘Construction around tree #25’ photograph taken on 19 February 2013 and included in Tree Dimension’s letter of 7 September 2015. He said that what took place near tree 25 was only ‘scraping the vegetation and slight excavation on the higher side’. He said that a ‘slight excavation along that whole edge’ was carried out. When asked to clarify whether this excavation occurred near tree 25, Davidson said ‘no, only scraping around the tree, only scraping of the vegetation and the slight topsoil, if you could say that’.
He said the slight excavation was ‘not completely’ in the vicinity of tree 25, ‘it would be between tree 25 and the central area’.
He agreed that, from the look of the photo, the scraping occurred within 3.6 meters of the tree, and that it was definitely within 14.9 metres of the tree.
The evidence established that Davidson scraped the ground in tree 25’s TPZ with a backhoe with an attached mud bucket to remove vegetation and level the ground. Davidson said:
We had to work in front of that tree, so we did end up scraping the soil so it's flatter, but just mainly the topsoil. So you could sit my machine on the top of the - and remove the soil for the cross pieces.
He said that he ‘only used the mud bucket on that area because, of the non-destructive purpose of the site’. He explained, by way of comparison, that a mud bucket is big, wide and has a blade which you use to scrape the ground, whereas a ‘disruptive bucket’ has teeth which allows you to dig the soil. He went on:
If you use a tooth bucket, you actually rip the ground or rip the surface you’re trying to dig in order to break it up. A mud bucket won’t do – it scrapes and it’s like a grader, and when you become – hit a big rock, it’ll just come up and won’t dig into it. It’ll hit it and then come up over the top, if you could imagine that.
He agreed that the mud bucket was made of steel, was 1.2 m wide, and the depth of the curve of the bucket was 600 mm/0.6metres. It had ‘a big blade on the edge’.
He said that when a mud bucket was used to scrape the ground ‘anything that’s there, soil, roots, will come along with that blade being scraped’.
He said he did not encounter any structural roots or large roots in the vicinity of tree 25 while carrying out his work. He gave evidence that any roots bigger than 4 inches would be ‘a very significant root that I wouldn’t be able to pull out’. However, he agreed that roots less than 4 inches would be caught up in the soil, in the scraping mechanism, but that ‘you would certainly feel.… you were moving slowly, but the bigger the root the more resistance it would get so your feel would be a root block’.
As the plaintiffs submit, the machinery Davidson used is ‘large, heavy and scrapes away (with the topsoil) all but the larger roots without any discrimination or care’.
Although I am satisfied that Davidson (and so Contek) did take some care in using that machinery – a more intrusive digging bucket was not attached to the backhoe, for example, and someone was ‘spotting’ for Davidson whilst he was driving it to see if there were major roots in the area the bucket was scraping in – the required minimisation of root disturbance did not occur.
[4.5.4] of AS 4970-2009, makes it clear that a backhoe should not be used in a tree’s TPZ. It states that necessary root pruning should be done with sharp tools such as secateurs, pruners, handsaws or chainsaws.
Such manual pruning is very different from using a machine with a bucket attached to scrape off the top level of the soil, bringing roots with it except where they are more than 4 inches thick.
I reject Contek’s submission that in undertaking the clearance of the site as he did, Davidson minimised disturbance to the roots in tree 25’s TPZ in this aspect of the construction of the boardwalk.
Contek refers to the engineering report for the construction and argues that topsoil was required to be removed from the area on which footing foundations were to rest. The report stated:
8.3 General Guide to Good Site Preparation
Footing systems rely on good construction practices for both short term and long term performance. The following guidelines (although not exhaustive) provide general information which will assist in good construction:
a)Topsoil containing grass roots or other organic material

should be removed from the area on to which footing foundations are expected to rest.
b)Removal of weak materials and / or topsoil will be required prior to placing rolled or controlled fill.
I accept that the topsoil needed to be removed. The issue is how it was removed.

Contek argues that council officers attended the site and supervised the works each day. This is beside the point.
Contek also points to the 7 September 2015 letter from Tree Dimensions. It indicates that on 19 February 2013, when all the pier holes had been dug, and excavation had been completed, council arborists attended the site and confirmed that ‘no damage to trees was observed’. However, those arborists did not give evidence, the letter does not mention tree roots, and what observations the arborists carried out could not be tested.
I accept Davidson’s evidence of how he carried out his work at the site. I am satisfied that the way it was done establishes that Contek did not minimise root disturbance in tree 25’s TPZ.
Proving that the root disturbance was not minimised is only the first step, however. The next step in the plaintiffs’ cause of action is to prove that this failure to minimise was a cause of the tree falling.
I am not satisfied of that.
The evidence did not establish the extent of the damage caused by the failure to minimise root disturbance.
I accept Davidson’s evidence that no major roots were encountered.
The evidence of how much of tree 25’s TPZ was affected by his excavation was scant.
The evidence did not establish how much of the minor excavation done by Davidson was within tree 25’s TPZ. More importantly, it did not establish how much of the TPZ was affected in terms of measurement or percentage.
AS 4970-2009 at [2.4] allows for up to 10 per cent of a tree’s TPZ to be affected in certain circumstances. The AIA report refers to this Australian Standard in indicating that up to 10 per cent of a tree’s TPZ may be encroached upon, in paragraphs [4.2], [4.3] and [4.3.2].
I prefer Hartley’s evidence as to causation.

B - Cutting roots in tree 25’s SRZ

Recommendation 2 of the AIA report provides that:
Trees being retained are to be protected during works. Roots must not be cut within their Structural Root Zones (SRZs).
The plaintiffs say that Contek breached this recommendation by cutting roots within tree 25’s SRZ.
I am satisfied on the balance of probabilities that Contek did cut roots within the SRZ.
Unlike other recommendations, which expressly refer to ‘structural’ roots, this recommendation is not limited to structural roots. The language is clear: ‘roots’ must not be cut within the SRZs of the trees that were to be retained.
Davidson’s evidence was that the use of the mud bucket would scrape smaller roots (less than 4 inches) away with the soil. I am satisfied that scraping of the topsoil would have severed roots less than 4 inches within tree 25’s SRZ.
Davidson accepted when giving evidence that from the look of a photo taken at the time of construction, his scraping would have been within 3.6 metres of the tree (that is, within the tree’s SRZ).
I am not satisfied that the breach caused the tree to fall.
There is no evidence of how much of the tree’s SRZ was affected.
I prefer Hartley’s evidence as to causation.

C - Not hand digging pier holes in tree 25’s SRZ and not repositioning the piers if structural roots were found in the SRZ

The plaintiffs allege the Contek breached recommendation 3 by not hand digging pier holes in tree 25’s SRZ and not repositioning the piers if structural roots were found.
Recommendation 3 of the AIA report states:
If piers are required within the SRZ of trees ≠ …25… holes should be dug by hand to 600mm depth to determine if major woody (structural) roots are present. If such roots are encountered, there must be scope to reposition the piers clear of woody roots. If no such roots are found, pier holes can be completed using mechanical means
I am not satisfied on the balance of probabilities that Contek failed to dig holes by hand in tree 25’s SRZ.
I am not satisfied that structural roots were found in tree 25’s SRZ.
It follows that I am not satisfied this alleged breach occurred.
I reject the plaintiffs’ submission that while the Court can accept that some of the pier holes in the vicinity of tree 25 were hand dug, the Court should find that some of the holes were mechanically dug.
Sinclair gave evidence that pier holes were hand dug in the northern end, but he could not recall the exact numbers. He said about 10 pier holes were dug in the tree protection zone of tree 25. He thought ‘five to 10’ of the holes were hand excavated but said he was guessing. Sinclair was not able to say where the mechanical drilling stopped and the hand-digging started. He said it was ‘possible’ some of the mechanical drilling occurred within 14 metres of tree 25.
Davidson gave evidence that ‘most of the holes’ along the boardwalk ‘were augured by the drill type machine … and then others were hand dug …’. He could not give direct evidence of the digging of the pier holes in the vicinity of tree 25. His evidence was: ‘I didn’t actually observe them but I know they were hand dug because of the sensitive area as well as the services in the area’.
The plaintiffs rely principally on an absence of evidence that holes dug in the SRZ were dug by hand. They say that Contek’s own evidence does not rule out the mechanical drilling of pier holes within the TPZ of tree 25. They point to the fact that Sinclair’s notes mention some holes specifically as being dug by hand in another area of the construction site, when gas/electricity lines were being searched for. They invite me to infer that because his notes do not mention the holes in the SRZ being dug by hand that this means they were dug by machine. They refer to ‘bored holes’ and ‘drilling’.
However, the fact that Sinclair did not make notes about hand digging holes in particular places does not persuade me that holes in those places were not hand dug. His notes were sparse, and patently did not include everything he observed in overseeing many people working on a project of this size over a number of days.
Although he was fairly new to his role when supervising this project, I am satisfied from his evidence that he is a conscientious person who was aware that the trees needed protection. He gave evidence of the initial meeting on 5 March when the arborist discussed this.
The plaintiffs also rely on Nicolle’s opinion that ‘roots were evidently severed in the excavation of these pier holes’.
When cross-examined about whether the damage to the roots in the photographs he relied on could have been caused by the removal of the tree after it fell, Nicolle said it was ‘possible’, but less likely than being damaged by the pier holes or the site cut ‘due to the position of those roots and the colour of the wood within those roots’. Nicolle explained in re-examination that the roots were ‘very close’ to the pier in the upper left-hand image, and that the position of the root adjacent to that pier ‘matches up with a borehole that would have been excavated to put that pier in’. Nicolle also explained how the colour of the wood helped him to determine how long ago the severance occurred. When asked how likely it was that the construction works caused the damage in the photographs, Nicolle said ‘highly likely’.
However, the fact that roots were severed does not mean that it was due to a mechanical dig occurring.
The two apprentices who dug the holes were not called and so there is no direct evidence as to what they did. The plaintiffs say I should draw a Jones v Dunkel (1959) 101 CLR 298 inference against Contek about the apprentices who dug the holes not being called to give evidence by Contek.
Jones v Dunkel permits the Court to draw an adverse inference against a party who does not call a witness who might have been expected to be called to give evidence about a matter, without satisfactory explanation. I can infer in such circumstances that such evidence would not have helped the case of that party, and more readily accept evidence to the contrary by other side.
However, here there is no evidence ‘to the contrary’ which I can ‘more readily accept’. The plaintiffs have not produced evidence that that the holes were not dug by hand. It was for the plaintiffs to prove their case. Jones v Dunkel is inapplicable.
Delaney inspected the root plate after the tree fell, and after the clean-up had occurred. In his report, he observed that one of two large roots which had been severed – the two roots being of approximately 17 centimetres and 20 centimetres in width – was ‘very close to one of the support piles for the boardwalk’.
An elevated board walk had been constructed within approximately 2 metres of the stem base. Based on on-site discussions with a representative of Com-Tek [sic] (builder of the boardwalk) on 16/10/2014 the boardwalk was completed around 18 months prior to the tree failing. The soil level on the west side of the tree was lowered to accommodate the boardwalk. Based on inspection of the root plate after the damaged sections of [the] boardwalk had been removed it was evident some roots had been severed. Most roots severed would have been quite small however two large roots of approximately 17centimetres and 20 centimetres had been severed/broken. Some brown rot was observed in the end of one of the roots which appears to be natural degradation at the broken end. This root was very close to one of the support piles for the boardwalk. The other root did not appear decayed probably because it was suspended in the air under the boardwalk once the soil levels had been lowered.
I accept that at that stage one of the roots which was broken was close to the support pile for the boardwalk. However, Delaney’s comments do not assist with whether that support pile was hand dug or not.
The plaintiffs bear the onus of satisfying me of the elements of their case on the balance of probability. I am not satisfied that these failures occurred.
Contek refers to the fact that on 19 February 2013, council arborists attended the site, after all digging of pier holes and excavation had been completed and confirmed that ‘no damage to trees was observed’. However, as indicated above, I do not give this any weight.
As project manager and site supervisor, Sinclair was onsite daily. He measured the various pier holes. He looked inside each of the holes which had been dug and did not observe any structural roots which had been cut.
Contek also submits that the issuing of the Certificate of Completion and payment of Contek’s invoice by the council, which oversaw the works on a daily basis, strongly infers that the works undertaken by Contek were performed in accordance with the contract, and the AIA Report which forms part of that contract.
I do not accept this inference arises.
Nicolle did not inspect the site, but gave evidence (based a photograph from Tree Dimensions) that ‘at least two, perhaps four’ piers were constructed within the SRZ of tree 25. That may be so; but it does not establish that structural roots were encountered and severed by the pier construction.
To the extent roots were severed, it may have been when power and gas lines were put in. Further, some damage to tree 25’s roots was likely to have occurred as the tree fell, and during the clean-up after it fell.
I am not satisfied on the balance of probabilities that Contek breached the requirements of the AIA report by failing to reposition structural roots encountered when digging occurred, and failing to reposition pier holes.
To find this breach occurred, I first need to be satisfied that structural roots were found in the SRZ, and then find that piers were not repositioned if this occurred.
If no major structural roots are encountered, AS 4970-2009 allows that roots can be dug mechanically.
There is no evidence on which I can be satisfied that if pier holes had been hand dug to 600 mm they would have encountered major structural roots. The recommendation allows for roots to be dug mechanically in any event if major structural roots are not encountered when hand digging occurs.
Sinclair gave some evidence that some roots were repositioned, but it was unclear whether he was referring to roots within the TPZ or SRZ of tree 25.
The evidence does not establish on the balance of probabilities that structural roots were cut in the SRZ because pier holes were not repositioned.
In any event, as indicated, I prefer Hartley’s evidence.

D - Not putting geotextile fabric, a layer of mulch and strapped boards where
there would be foot traffic/equipment in tree 25’s TPZ

Recommendation 4 requires that various tree protection measures be implemented during all site works. One of these was tree protection measure 2:
Within Tree Protection Zones (see Table 2) the ground must be protected from compaction from foot traffic and equipment, machinery and materials. Where any such use of Tree Protection Zones is required, the area must first be covered with geotextile fabric, then a layer of mulch such as woodchip to a minimum depth of 100mm, and covered by strapped boards.
I am satisfied that Contek did not comply with this tree protection measure and hence this recommendation.
Davidson gave evidence that mulch was put down to protect the ground from the excavator. However, when asked if he ‘undertook that task also for anywhere where the heavy machinery would be on the ground’, he responded ‘not specifically everywhere, no’. When Davidson was asked if he recalled a process of ‘covering the ground in geotextile fabric, covering it with mulch and then putting strapped boards on top’ he said ‘no’.
Contek’s documentation for the worksite is consistent with Davidson’s evidence. The documentation makes reference to mulch for the excavator path (but not in relation to other heavy equipment), does not refer to the placement of geotextile fabric for the purpose of protection from compaction, and does not refer at all to strapped boards.
It is not clear if geotextile fabric was put down before foot traffic and equipment and machinery occurred in the TPZ. However, I am satisfied that the ground was not covered with strapped boards. When asked whether measures in relation to the excavator path included wooden strapped boards or the placing of geotextile fabric, Sinclair said: ‘I’m unsure on the geotextile but not the replaced boards’.
The language used in this recommendation is mandatory: the ground ‘must’ be protected, the area ‘must first be covered …’. That did not occur.
Contek argued that the plaintiffs need to establish on the balance of probabilities that the soil in the vicinity of Tree 25 was actually compacted by heavy vehicles and foot traffic. It said that while evidence was elicited from Davidson that his backhoe was used in the vicinity of the tree (within 14.9 metres of it), and that he accessed the area at the northern end of the site from the swale and then backed up the bank and went along the top of the bank so that he could clear it with his mud-bucket, that is as high as the evidence got for the plaintiffs. However, given the reference to foot traffic, I am satisfied that some compaction of the sort contemplated by the tree protection measure did occur.
However, I am not satisfied this was a cause of the tree falling.

At the time of the works, within tree 25’s TPZ there was a compacted path, there was Monbulk Road, and there were power cables and gas cables - each installed in their specific trenches.
There was no evidence as to how often and for how long Davidson’s backhoe was in tree 25’s TPZ. Nor as to where in the TPZ his backhoe was – it could have been close, within its SRZ, or as far out as the kerb of Monbulk Road, given that the arm of Davidson’s backhoe had a twenty-four foot reach when scraping the ground.
Nor was there evidence as to whether or not the soil was in fact compacted near tree 25 following excavation, or which section of it was compacted (above or below or all around the tree). Nor as to the surface area of compaction in the vicinity of tree 25. Nor as to the degree of compaction of the soil in tree 25’s TPZ.
There was no evidence of what effect mulch, if it was near tree 25’s TPZ, on its own had against compaction or, by comparison, how much compaction there would have been had mulch, geotextile fabric and strapped boards all been used in the vicinity of the tree.
Whilst I accept it is likely that some soil was compacted in the TPZ by Davidson’s backhoe, and by foot traffic, I am not satisfied that such compaction caused or was likely to have caused damage to the roots of the tree, or that it was a cause of its falling.

E - Putting rock ballast or beaching in tree 25’s TPZ

The plaintiffs say compaction was also caused by rock ballast being deposited near the tree. They say this was a breach of tree protection measure 2:
Within Tree Protection Zones (see Table 2) the ground must be protected from compaction from foot traffic and equipment, machinery and materials. Where any such use of Tree Protection Zones is required, the area must first be covered with geotextile fabric, then a layer of mulch such as woodchip to a minimum depth of 100mm, and covered by strapped boards.
At [4.5.3] the AIA states:
If temporary access for machinery is required within the TPZ ground protection measures will be required. The purpose of ground protection is to prevent root damage and soil compaction within the TPZ. Measures may include a permeable membrane such as geotextile fabric beneath a layer of mulch or crushed rock below rumble boards as per Figure 4.
The plaintiffs submit that the placement of the beaching rock within the TPZ of tree 25 constituted ‘compaction from … materials’ on the site, and therefore Contek needed to protect the TPZ of tree 25 in undertaking that work. They said that it is clear from the evidence that Contek did not consider the potential impact of the rock beaching on the TPZ of tree 25 at all, and that there is no evidence of any measures being put in place to protect the tree’s TPZ from that compaction.
I am satisfied that the relevant tree protection measure applied during site works. It is directed to protecting the ground at that time, not to preventing compaction afterwards. Notably the tree protection measure allows for a layer of rocks to be put on the ground.
Contek submitted that the crushed rock was required to be installed in the swale (a high drainage area) under a variation to the contract, in order to prevent potentially destructive erosion in the region of tree 25.
I accept that there was evidence that a significant amount of rock beaching was placed in the swale drain. Contek’s site documentation records 7.63 tonnes of beaching rock was received from Boral. Sinclair gave evidence that the beaching rock was used to stop erosion. Given the location of the swale in relation to tree 25, I am satisfied that it is likely that at least part of the beaching rock was placed within the TPZ of tree 25.
Sinclair, when asked if he recalled seeking an arborist’s opinion about the placement of the beaching rock, said ‘no, we put the beaching rock down to stop erosion occurring’.
Even if I had found putting down the rock beaching to be a breach of the AIA report I would not have been satisfied that it was a cause of the tree falling.
I prefer Hartley’s evidence, as indicated.

F - Not having an arborist onsite to supervise the excavation works

I am satisfied that an arborist was not on site to supervise at all necessary times. However, I am not satisfied that this was a cause of the tree falling.
As stated above, recommendation 4 of the AIA report requires that various protection measures be implemented during all site works. Tree protection measure 3 states:
For any excavation within Tree Protection Zones … the project arborist should be onsite to supervise the works.
[1.4.4] of AS 4970-2009 defines the term ‘Project arborist’ as:
The person responsible for carrying out the tree assessment, report preparation, consultation with designers, specifying tree protection measures, monitoring and certification. The project arborist will be suitably experienced and competent in arboriculture, having acquired through training, qualification (minimum Australian Qualification Framework (AQF) Level 5, Diploma of Horticulture (Arboriculture)) and/or equivalent experience, the knowledge and skills enabling that person to perform the tasks required by this Standard.

[4.1] of AS 4970-2009 states:
…
Some works and activities within the TPZ may be authorized by the determining authority. These must be supervised by the project arborist. Any additional encroachment that becomes necessary as the site works progress must be reviewed by the project arborist and be acceptable to the determining authority before being carried out.
[4.5.4] states:
Some approved works within the TPZ, such as regrading, installation of piers or landscaping may have the potential to damage roots.
If the grade is to be raised the material should be coarser or more porous than the underlying material. Depth and compaction should be minimized.
Manual excavation should be carried out under the supervision of the project arborist to identify roots critical to tree stability. Relocation or redesign of works may be required.
[5] of AS 4970-2009 details the monitoring and certification required by the project arborist. It includes the need for a preconstruction meeting to be attended by the site manager, the project arborist and contractors to introduce the tree protection plan and its requirements. At [5.4.1] it sets out that:
In order to ensure that protection measures are being adhered to during the pre-construction and construction stages, there should be a predetermined number of site inspections carried out by the project arborist. Matters to be monitored and reported should include tree condition, tree protection measures and impact of site works which may arise from changes to the approved plans
At [5.4.2] it sets out that:
The project arborist will monitor the impacts of demolition, bulk earth works, installation of temporary infrastructure…
…
At completion of site establishment, the project arborist should certify that tree protection measures comply with the tree protection plan.
At [5.4.3] it provides:
The project arborist will monitor the impacts of general construction works on retained trees. Monitoring should be done at regular intervals or in consultation with the site manager. Monitoring is to be recorded for inclusion in certification at practical completion.
Critical stages typically include installation of services, footings and slabs, scaffolding, works within the TPZ and at completion of building works.
[5.4.5] states:
Practical completion assumes that all construction and landscaping works are finished. At practical completion all remaining tree protection measures should be removed. The project arborist should assess tree condition and provide certification of tree protection.
[5.5.2] provides for final certification to be given:
The project arborist should assess the condition of trees and the growing environment and make recommendations for any necessary remedial actions.
Following the final inspection and the completion of any remedial works, the project arborist should certify (as appropriate) that the completed works have been carried out in compliance with the approved plans and specifications for tree protection …
The letter from Tree Dimensions of 7 September 2015 states that two inspections occurred: the first on 5 February 2013 (the letter states ‘at this stage tree removals were being done and the area was being mulched); and the second on 19 February 2013 (‘to photograph the progress of works’). The letter states: ‘apart from these inspections we were not asked to inspect the site during the works’.
There is no reference in this letter to Tree Dimensions being asked to supervise excavation works.
Contek’s documentation does not record Tree Dimensions or any other arborist attending the site when excavation work was being undertaken.
Davidson, who undertook excavation work including the clearing of the site using the mud-bucket, was asked if he was aware of a project arborist being on site and he said ‘I never met the arborist, no’. If an arborist had been supervising the excavation works, it is to be expected Davidson would have met that arborist.
Although Sinclair had sent an email to the council on 6 May 2015 stating that ‘Tree Logic’ had inspected ‘all … excavations, there is no documentation at all supporting the involvement of a company called Tree Logic. When it was put to him in cross-examination that there was no material from Tree Logic by way of a letter of engagement, invoices, emails and the like, he said he ‘may have made an assumption and assumed the wrong name of the arborist’. Sinclair then said, ‘the email probably should have read “an arborist attended”’. When he was asked if he was saying that it would have been more correct to say that an arborist attended, rather than supervised, he responded ‘yes’.
I am satisfied that Sinclair’s concession was correct. The excavation works at the site were not supervised – in the sense required by the AIA report - by any arborist, let alone a ‘project arborist’.
Contek submitted that the excavation works were adequately supervised onsite by the council’s arborist who inspected the site, both before (5 February 2013) and after (19 February 2013) the excavation and digging which were undertaken by Contek between 7 and 13 February 2013 and who noted ‘no damage to trees was observed’.
The invoice for ‘Arboricultural consultancy services Monbulk Road, Belgrave: boardwalk project. Supervision of works near trees, onsite meetings and advice January/February 2013’ showed just 2 hours of work done.
I am satisfied that the inspections and other work carried out, amounting to some two hours’ work invoiced, does not amount to the supervision of the project to the degree required by the AIA report, and under AS 4790-2009.
However, the tree fell because of physical factors affecting it, not because an onsite arborist did not adequately supervise the work. This case does not involve a hypothetical as to what might have happened had an arborist supervised adequately.
I am not satisfied that any of the physical factors relied on by the plaintiffs were a cause of the tree falling.

DR NICOLLE’S EVIDENCE

Nicolle was of the view that every one of the breaches of the AIA report alleged by the plaintiffs was independently a cause of the tree falling, and that each such breach would by itself (even without other causes being established) – in combination with the tree’s characteristics and the natural forces being applied to the tree – have caused the tree to fall.

Communication with solicitors

Dr Nicolle was first contacted by a solicitor at Lander & Rogers, the solicitors for the plaintiffs. He does not remember when he was first called, or what was explained to him about the case.
On 8 March 2016, the solicitor sent him an email, which referred to wanting verbal advice to be provided:
Dear Dean,
Thankyou for your time today.
I would be grateful if you could provide an estimate and let us know your hourly rate. We anticipate that it will take approximately 4-6 hours to review the documentation and then perhaps allow 2 hours of verbal advice.
The next day Nicolle responded, indicating he would form an opinion over the next few weeks:
As discussed yesterday, my rate is $160/hour (inc. GST). I can make time to review the documents and form an opinion over the next few weeks.
Nicolle gave evidence that he knew at this stage that his opinion was sought about the cause of the failure of tree 25 and he understood he was being asked to give an oral not written opinion that stage.
On 22 March 2016, Nicolle was sent a link to download some electronic documents.
On 24 March 2016, he was asked by email to provide ‘verbal advice only’ and to ‘refrain from sending … any written views at this stage’.
He was given hard copy documents by the solicitor on 30 March.
On 6 April 2016, the solicitor made a diary note about a conference he had with Nicolle:
I received a phone call from Dean Nicolle on [number omitted] at 11.16am on 6 April 2016.
Dean and I discussed the claim generally and his view of the matter. I asked him that the key question we need to know is whether or not in his view the boardwalk works caused the tree to collapse. He said that it was a significant contributory factor. I explained at great length the legal standard required to satisfy causation, that being the balance of probabilities and that that cause needs to be elevated as a dominant operating or casual factor. In the context of the current claim we discussed what the boardwalk work means and specifically the work that was done to remove the soil and also to resolving in the severance of roots and the installation of the rock beaching,
We spent great length looking at the inspection report that was done after the tree, and specifically tree number three. Ultimately we concluded that this was not the tree that fell and in fact that report was completed at a time that was after the boardwalk works. For that reason that tree was not relevant.
Ultimately he said that in light of all these circumstances with the tree he would be able to say that the boardwalk work were a major contributing factor. That is that they as contributing factors should be elevated above others. In this regard he said the tree is probably 40 or 50 years old and ordinarily mountain ashes would stand for 100 to 200 years so the proximity of the failure of the tree to the boardwalk works in the context of the tree’s age would suggest that it was an operating casual factor. We discussed the operation of rot and how the tree essentially when healthy outgrows the rot and it [is] not unusual to see rot in a tree of this age in the circumstances it is in.
In terms of the next steps I said that I would be meeting with the client tomorrow to discuss his preliminary views and that I would like to discuss this further with him with a colleague of mine in the next two to three weeks. In the meantime I asked him to familiarise with the report of council and also the project reports indicating what was done during the construction as well as the reports of tree dimensions.
Dean said that he would do that and await contact from me to discuss with him.
During cross-examination, Nicolle was asked about this diary note. He agreed that by 6 April he had formed a preliminary opinion regarding the cause of the failure of the tree: characteristics of tree; weather conditions; construction works.
He was asked about the language of the note:
All right. When it says, if you look here in the language that he uses in his diary note on 6 April when it makes reference to "we discussed", "we spent", "we concluded", you and [the solicitor] were having conversation about the tree's failure together, weren't you?---Yes.
All right. You were both trying to work out together how it was that the tree had failed by him giving you aspects of evidence and you providing to him various - or opining or forensically trying to ascertain why it is that the tree failed?---No, I disagree with that. The manner in that [the solicitor] was directing me was in the evidence he provided me and the questions that were asked.
Nicolle said that he thought his own diary note of the conversation would have been a bit different. He said that the solicitor was directing him to the aspects he was more interested in.
He disagreed that he knew pretty early on that Lander & Rogers were acting for the plaintiffs, saying that he knew they were acting for one side or another. He later said that ‘it was probably explained to me’ who they were acting for and that he did not ‘fully understand what the plaintiff is’. (To the extent it is suggested that this shows how disinterested a witness he was, I do not accept that. He must have been aware his evidence was being sought by someone wanting to establish that a cause of the tree falling was the construction of the boardwalk.)
Asked about the reference to ‘legal standards’ and need for something to be a ‘dominant operating’ or ‘causal factor’ he said, ‘I don’t fully understand what that means, because that’s legal speech’. He said his reasons for the tree’s failure are in his report.
He said it was standard practice for him to give oral advice first.
On 11 May 2016, he was sent the letter of instruction mentioned in his report.
The letter stated that it retained him as an independent expert. It was formally addressed to Mr D Nicolle, and started ‘Dear Mr Nicolle’ (rather than ‘Dear Dean’, as was the tenor of emails already sent by the solicitor). It went on to set out that Lander & Rogers acted on behalf of the insurers of the owner and occupier of the Micawber tavern. It referred to the fact a tree fell and damaged the tavern on 2 August 2014, noting that the tree was located in close proximity to a boardwalk which was constructed in about 2013.
It went on:
Expert report
We have previously provided you with documentation relating to the construction process and subsequent inspections performed after the Tree collapsed including:
(a) documents relating to the construction of the boardwalk


obtained under Freedom of Information Request;
(b)   photographs of the Tree and its root-ball following the collapse;
(c) Arboricultural Impacts Assessment report prepared by Tree


Dimensions dated 17 June 2011 (AIA Report); and
(d) Yarra Ranges Report Inspection Report dated 23 October 2014

       (Yarra Ranges Report).
Having reviewed the documentation, we now request that you prepare a report addressing your opinion on the cause of the Tree collapse.
Please:
(a) provide a background on the Mountain Ash species;
(b) advise whether the requirements of the AIA report were adhered to and identified any relevant breaches, referencing the relevant documents that demonstrate any breaches;
(c) advise the relevant standards, codes, regulations and good industry practises relevant to conducting works in close proximity to the Tree and identify any relevant breaches, referencing the relevant documents that demonstrate any breaches;
(d) advise the expected lifespan of a Mountain Ash located in the position of the Tree and identify the approximate age of the Tree when it collapsed;
(e) state what in your opinion was the cause of the Tree collapse; and
(f)   address the comments and conclusions made in the Yarra Ranges Report.
Expert Witness Requirements
As your report may be used in court proceedings, we enclose a copy of the Expert Witness Code of Conduct in Form 44A of the Supreme Court (General Civil Procedure) Rules 2005 and Expert Witness Information Sheet in relation to the overarching obligations imposed under the Civil Procedure Act 2010.
Please consider these in preparation of your report and acknowledge that you have done so in your report.
If you have any queries, please do not hesitate to contact us. Otherwise, we look forward to receiving you report at your earliest convenience.
On 15 May, Nicolle sent a quote:
My hourly rate remains at $160/hr (inc. GST). It would take me approximately 36 hours to address, and provide a written report on, the six broad questions that you have provided in your letter dated 11 May 2016. My estimated fee for the preparation of the report is therefore $5,760.
On 18 May, he was sent an email by the solicitor asking him to proceed and stating:
Thanks Dean, please proceed.
…
Please give us a call if you are unsure about anything and also please ensure that you issue a draft first.
The letter of instruction did not refer to a draft report being requested.
He prepared a first draft report dated 25 June 2016.
He gave evidence that this first draft was consistent with his verbal advice previously provided.
At [4.4.1] of this first draft, he asks a couple of questions about two photos he mentions, highlighted in green in the draft report: ‘photograph 5 on page 13’ of the FMG Engineering Report of 18 August 2014, and the 8th of nine unnumbered photographs included in a letter by David Galwey of Tree Dimensions dated 7 September 2015. The wording of his question is:
do you need this image reproduced and marked up here?
Asked about these queries he said that he wanted to know if he could use other people’s images as there might be copyright issues and he wanted to know from the solicitor if he could put the photos in.
The solicitor’s diary note of 28 June, records a telephone call from Nicolle that day: Relevantly, it says:
He said he had prepared a draft of his report in line with his previous advice. I said please send through the report. He had some questions about whether to include photographs and pictures of documents. I said I would have a look at the report and let him know but generally speaking it should be included but not to the point it affects the way in which the report flows. If it is an important document to refer to that forms a basis of his opinion then it might be good to include as an appendices.
Nicolle emailed the draft report to the solicitor about twenty minutes later, at 12.47 pm:
As discussed, attached is my draft report for the Micawber Tavern tree collapse matter. I have not proof read the draft as yet, and you will see highlighted sections requiring your comment. I look forward to your feedback.
I reject Nicolle’s evidence that his reason for asking in the draft, ‘do you need this image reproduced’, was in order to clarify the copyright position of the images. The diary note the solicitor made does not mention copyright. If that had been Nicolle’s motivation, one would expect the words he used to have been along the lines of ‘Can I/Am I allowed to reproduce this image here’. Instead the words used were: ‘do you need this image reproduced’ here. This is arguably symptomatic of trying to satisfy what the solicitor ‘needs’. At its highest, it might have been considered to have been intended to offer something to satisfy the solicitor’s ‘need’ to make the report clearer – but this is not what Nicolle said in evidence about the motivation. The wording appears to me to be a step away from being independent: Nicolle is directing his report to what the solicitor for those briefing him ‘needs’. It is also an example of evasive evidence being given by Nicolle.
Nicolle sent an invoice on 4 July for 36 hours work in relation to ‘written report tree collapse’ and claiming $5,760. This was consistent with his earlier quote.
On 21 July, the solicitor emailed Nicolle asking him to arrange a time to discuss the report on the following Monday. The next day Nicolle replied agreeing to the meeting.
The solicitor sent an outlook calendar invitation for a call on 25 July, which Nicolle accepted on 24 July. Nicolle did not recall if he had that conversation on 25 July, but accepted that if he had a conversation about the first report, it was most likely on 25 July.
I am satisfied, given the emails and calendar invitation, that Nicolle and the solicitor did have a further discussion before the provision of the second draft report – probably on 25 July.
On 3 August, Nicolle wrote saying:
I am working through the draft of the report re the Micawber Tavern tree collapse. Can you please provide me with the list of documents and images provided to me, so I cane [sic] paste/reformat it into an appendix of the report?
On 22 August, Nicolle sent an email attaching the second draft report dated 19 August 2016, and noting:
…Let me know if you require any further information at this stage.
Please note that I will be interstate in the field from the 24th August to 18th September inclusive, and I will be unable to attend to any amendments to the report during that time.
Nicolle said in evidence that the amendments he had in mind would only be minor amendments such as typos he contemplated at that time:
The point I was trying to get across, that is, I wouldn't have access to my computer during that time, so if there were any typos or editorial issues or if it needed to be turned into a final report, I couldn't do that during that time.
Nicolle sent an invoice on 24 August. It sets out the amounts claimed in the first invoice again, and added a claim for a further $1,440 for 9 hours work – with the date for that further work recorded as 2 August. The description given to the 9 hours of work was ‘Report expansion/amend’.

I am satisfied that he discussed the contents of the first draft report with the solicitor, and made some significant changes to the second draft report after that discussion.
I am satisfied that Nicolle initially intended the first draft report to be in substance his final report. His invoice for the first draft report was for precisely 36 hours’ work: the amount of his initial estimate of this time for providing the report.
The first draft report left a couple of minor points needing finalising: he wanted answers to his questions about images, and was waiting for the Bureau of Meteorology data. Minor typographical or formatting changes would also have been envisaged, with time to re-read the draft again. But there were then significant changes made to the second draft report.

Diary notes

A diary note made by the solicitor of a discussion he had with Nicolle on 16 October 2018 – a few weeks before trial – uses the phrase ‘before we planned on a solid answer’:
I told him that it had been a while since we had last spoken but the matter is now going to trial on 13 November 2018 and I just wanted to discuss a further question with him. I asked him how he thought of the hypothetical situation of an arborist having been called in once the construction works were finished would have played out. He said that it was difficult to say and it depends on the amount of information that the arborist was given, what their scope of instructions were and whether the extent to which the site had been remediated. I asked him if they were aware of the site cut and the method with which the piles had been dug and assumed you could see the root under the board walk what would he have thought. He said that he would have deemed the tree a serious risk. I tried to explain the hypothetical counter factual inquiry to be made with more detail however before we planned on a solid answer, the phone cut out. I presumed Mr Nicolle ran out of reception.
Nicolle said he recalled this conversation because he was driving at the time.
Mr Hayes QC cross-examined him about the words the solicitor used ‘before we planned on a solid answer’. Nicolle said:
... you discussed how you might respond to these types of questions or how you might give evidence on this topic with [the solicitor] on 16 October 2018 --- I didn’t understand it as that at the time and – – –
Well – sorry, go on? --- I just understood it as being asked hypothetical question about the subject tree – – –
Yes? – – – and me providing advice based on that question
But the words he says, “However, before we planned on a solid answer”, do you see those words? – – Yes. I can’t comment on why [the solicitor] used those words or why he writes the way he writes.
What I’m suggesting to you is that you were discussing your evidence with him in a way in which you could give evidence favourable to his client in response to this line of questioning that I’m asking you about the moment? – – – I didn’t see it that way from my end of the phone call, but I don’t know what the motive was from the other end.
The solicitor’s reference to the phone cutting out before ‘we planned on a solid answer’ is concerning. It raises concerns about the independence of Nicolle and the suggestion that he and the solicitor together were planning responses. I accept that Nicolle may not have seen it that way. I accept that the solicitor also may not have intended it in that way. However, the solicitor was not called to explain those words and in the absence of explanation it seems to me that they raise the concerns mentioned.
They echo the earlier phrase ‘we concluded’ in the solicitor’s diary note made at the outset, on 6 April 2016, where he wrote of his conversation with Nicolle:
We spent great length looking at the inspection report that was done after the tree, and specifically tree number three. Ultimately we concluded that this was not the tree that fell and in fact that report was completed at a time that was after the boardwalk works. For that reason that tree was not relevant.
Nicolle was asked about this:
All right. When it says, if you look here in the language that he uses in his diary note on 6 April when it makes reference to "we discussed", "we spent", "we concluded", you and [the solicitor] were having conversation about the tree's failure together, weren't you?---Yes.
All right. You were both trying to work out together how it was that the tree had failed by him giving you aspects of evidence and you providing to him various - or opining or forensically trying to ascertain why it is that the tree failed?---No, I disagree with that. The manner in that [the solicitor] was directing me was in the evidence he provided me and the questions that were asked.
Nicolle’s independence

I do not give the weight I otherwise would to Nicolle’s evidence as I have concerns in relation to his independence.
Nicolle disagreed he was acting as an advocate for Lander & Rogers’ client: he said he took ‘great pride in telling it how it is’. He maintained that he was not provided with any new assumptions in the various conversations he had with solicitors. He maintained that all opinions and findings were his own.
Neither the final report nor the supplementary report mentioned that Nicolle had provided earlier drafts to the solicitor, nor did they mention any of Nicolle’s telephone conversations or meetings with the solicitor. Nicolle gave evidence that he would have been happy to include that information had he known it was required.
The difficulty is that the Court cannot be sure what was said to Nicolle in those conversations that may have subtly affected the opinions Nicolle set out in the draft reports, and hence the final reports.
I cannot be sure what opinions were formed in his discussions with the solicitor even before the formal retainer letter was sent.
The initial request to him was for a verbal advice only – he was specifically told to produce nothing in writing at that stage.
He then charged 36 hours for his first draft report. This included two conferences in relation to the substance of his opinion – one of 1.5 hours and one of one hour.
Having provided his first draft report he then charged for a further nine hours – which included at least one conference – and made changes to it.
In the second draft report a number of opinions had either been added to or subtly altered.
It is most unsatisfactory for an expert to be approached to the extent Nicolle was before being formally retained with the ‘on the record’ letter of instruction. I do not accept Contek’s submission that the letter amounted to being a pantomime, but it patently does not disclose all the previous discussions that had occurred.
I note that this is not a case where it was put to me, or the evidence established that, the solicitor had made material changes to the body of the report, which the expert then accepted.
Nor is it a case where an expert’s report was changed by the expert, or by someone with his authority, on the instructions of counsel: see Hudspeth v Scholastic Cleaning And Consultancy Services Pty Ltd & Ors (No 8) [2014] VSC 567.
Hudspeth concerned whether the expert breached his overarching obligation.
Dixon J there stated at [54]:
Five observations can be made about this process. First, Mr Dohrmann accepts that Ms Atkins acted with his authority and he accepts responsibility for the second version of his report. Second, the date of the report was not changed and no note was added informing the reader that the report was revised on 1 July 2010. Third, section 3 of the report where Mr Dohrmann’s sources were recorded, was not amended to record that additional instructions were provided orally by the solicitors on 1 July 2010. Fourth, the changes that were made to the text of the report were not tracked or otherwise identified. Fifth, the fact that the report was amended was disguised by the overwriting process, by which an electronic copy of the first version was lost.
At [209]:
In essence, the different versions of the report were not identified as such and Mr Dohrmann did not record in the report his instructions to amend it.
Dixon J sets out the purpose and relevant parts of the Civil Procedure Act 2010 (Vic) (‘CPA’), including how it relates to experts: see [27 – 31]. At [29 – 30]:
[29] The participants in a civil proceeding, which means any proceeding in a court other than a criminal proceeding or quasi-criminal proceeding and includes an action for damages before a judge and a jury of six, are determined by reference to s 10 of the Act. That section states:
(1)       The overarching obligations apply to—
…
(b)       any legal practitioner or other representative acting for or on
          behalf of a party;
(c)       any law practice acting for or on behalf of a party;
…
(3)       The overarching obligations (other than the overarching
          obligations specified in sections 18, 19, 22 and 26) apply to any
          expert witness in a civil proceeding.
Expert witness is a defined term. Section 16 provides that each person to whom the overarching obligations apply has a paramount duty to the court to further the administration of justice in relation to any civil proceeding in which that person is involved.
[30] The overarching obligations that are presently relevant are stated by
       ss21 and 26 which are in the following terms:
[21] Overarching obligation not to mislead or deceive
A person to whom the overarching obligations apply must not, in
        respect of a civil proceeding, engage in conduct which is—
(a)   misleading or deceptive; or

(b)   likely to mislead or deceive.
…
At [36]:
…the relevant rules governing the preparation and use of expert evidence in civil proceedings were set out in Order 44 of the Supreme Court (General Civil Procedure) Rules 2005 and the Expert Code of Conduct. The Code is found in Form 44A to the Rules. The Rules are now supplemented by the Civil Procedure Act. Order 44 defines ‘expert’ in the same terms as the Act...
At [38] he sets out relevant parts of the expert witness code of conduct:
Expert Witness Code of Conduct
1.A person engaged as an expert witness has an overriding duty to assist the Court impartially on matters relevant to the area of expertise of the witness.
2.An expert witness is not an advocate for a party.
3.Every report prepared by an expert witness for the use of the Court shall state the opinion or opinions of the expert and shall state, specify or provide … [the matters set out in r 44.03(2)]…
4.Where an expert witness has provided to a party (or that party's legal representative) a report for the use of the Court, and the expert thereafter changes his or her opinion on a material matter, the expert shall forthwith provide to the party (or that party's legal representative) a supplementary report which shall state, specify or provide the information referred to in paragraphs (a), (d), (e), (g), (h), (i) and (j) of clause 3 of this code and, if applicable, paragraph (f) of that clause.
5.If directed to do so by the Court, an expert witness shall—
(a) confer with any other expert witness; and
(b) provide the Court with a joint report specifying (as the case requires) matters agreed and matters not agreed and the reasons for the experts not agreeing.
6.Each expert witness shall exercise his or her independent judgment in relation to every conference in which the expert participates pursuant to a direction of the Court and in relation to each report thereafter provided, and shall not act on any instruction or request to withhold or avoid agreement.
Dixon J states: ‘Primarily, the law of evidence and rules of court, notably the Expert Code of Conduct, regulate expert evidence’: at [139].
And at [141]:
The Expert Code deals not with admissibility of opinion but with the manner in which the courts regulate the preparation and presentation of expert evidence. The Code emphasises, primarily by requiring acknowledgement of adherence to it before an expert’s opinion is ordinarily admissible, that the expert owes to the court a duty to impartially assist the court to form a correct judgment on matters about which judges, or juries, are not knowledgeable. This duty is paramount, and it is owed to the court not to a party to whom an expert may owe other duties arising from contract or in tort. An expert must not be an advocate for a party.
In Makita (Australia) Pty Ltd v Sprowles (2001) 52 NSWLR 705, [79] Heydon JA referred to a list of duties and responsibilities of expert witnesses in civil cases, as stated by Cresswell J in National Justice Compania Naviera SA v Prudential Assurance Co Ltd [1993] 2 Lloyd's Rep 68. Heydon JA commented that this list ‘has been influential both in causing rules of court to be devised in this and other jurisdictions to control expert evidence and in later judicial pronouncements’. Dixon J refers to this list, in Hudspeth [142]:
1. Expert evidence presented to the Court should be, and should be seen to be, the independent product of the expert uninfluenced as to form or content by the exigencies of litigation (Whitehouse v Jordan [1980] UKHL 12; [1981] 1 WLR 246 at p 256, per Lord Wilberforce).
…
Dixon J noted, at [147], what was said by Ormiston JA in FGT Custodians Pty Ltd (formerly Feingold Partners Pty Ltd) v Fagenblat [2003] VSCA 33, [15] and [17] (Chernov and Eames JJA agreeing) about the Expert Code of Conduct:
[A]ll that has been said, particularly in recent years, about the desirability of expert witnesses providing independent evidence by way of opinion to the courts should be seen as expressions of the ideal manner in which expert witnesses should go about their tasks and the resultant opinions which those witnesses should strive to express. With but a few minor exceptions, none of them should be treated as stating principles of the law of evidence but they should be seen rather as admonitions to those who would give expert evidence, especially as to the way they should prepare and present that evidence to courts, if they and their clients wish it to be acted upon.
…
Dixon J said at [167]:
… lawyers should not ‘settle’ the evidence of experts, who must remain true to the Expert Code. The undisclosed settling of an expert’s report by a lawyer could place the expert in breach of the Expert Code, and the lawyer in breach of his or her duty to the court, if the expert’s evidence was changed or modified in a material respect. [citation omitted]
Emerton J dealt with non-disclosure issues in Secretary to the Department of Business and Innovation v Murdesk Investments Pty Ltd [2011] VSC 581 (ruling) and Secretary to the Department of Business and Innovation v Murdesk Investments Pty Ltd [2012] VSC 319 (judgment).
In the ruling, at [85] Emerton J set out the alleged breaches of the CPA:
The contraventions of the overarching obligation not to mislead or deceive are submitted to be as follows:
(a)…
(b)Mr Holland, Mr Murray and Mr Wallace [the experts] failed to disclose the meetings, communications and other exchanges that they had with Mr Dickey and/or his advisers;
(c)The declaration provided by each witness that no matter of significance which the witness regarded as relevant had to the knowledge of the witness been withheld from the Court pursuant to clause 3(h) of the Expert Witness Code of Conduct was misleading; and
(d)Mr Holland, Mr Murray and Mr Wallace [the experts] failed to comply with clauses 3(d), (e) and (g) of the Expert Witness Code of Conduct in that they did not disclose all of the facts, matters and assumptions upon which its opinion expressed in their reports were based or the reasons for each such opinion or all investigations upon which they had relied.
Her Honour found at [98 – 99]:
I accept the Secretary’s submission that Mr Holland and Mr Murray did not adequately disclose in their reports their dealings with Mr Dickey and Murdesk’s advisers. However, material exposing those dealings has been produced to the Secretary through the usual processes available to parties in civil litigation. The experts have given evidence about their dealings with Mr Dickey and/or his advisers, and their expert evidence has been tested by reference to that evidence and to the discovered/subpoenaed material. The Secretary has had the opportunity to properly test the expert evidence adduced by Murdesk by reference to these dealings with the client and its advisers and has not, in my view, been prejudiced by the non-disclosure.
Accordingly, the Court will not exercise its discretion to exclude the expert opinions on that basis. The expert opinions that have been challenged are probative and potentially of assistance to the Court, and the Secretary has not been prejudiced by any want of disclosure in the expert reports.
At [100], her Honour considered the submissions that the evidence of two experts should be excluded because ‘they were not impartial as required by clause 1 of the Expert Witness Code of Conduct and became advocates for the defendant in breach of clause 2.’ At [101] Emerton J stated:
The question of independence and whether expert opinions were genuinely held was considered by Brooking J in Phosphate Cooperative Co of Australia Pty Ltd v Shears, in which his Honour refused to approve a company scheme supported by an independent expert’s report as to the value of the company because he was not satisfied that the expert opinion was genuinely held. Justice Brooking emphasised that the guiding principle for expert reports is for care to be taken to avoid any communication which may undermine, or appear to undermine, the independence of the expert. In the case before him, the report was produced under the supervision of the company and its advisers and owed much to their exertions. His Honour held that it did not represent the genuine independent opinion of its authors.
Then at [106 – 108], Emerton J further explained the conduct:
Mr Holland repeatedly provided drafts of his reports and/or proposed sections of his reports to Mr Dickey for review. Mr Murray provided draft schedules of sales to Murdesk’s lawyers. Although there was no evidence of ‘vetting’ the witnesses prior to retaining them to ensure that their approach accorded with the interests of Murdesk, two of the three expert valuers retained by Murdesk had previously provided it with valuations for the land and had been involved in earlier proceedings on its behalf. Mr Holland, in particular, was a known commodity and had a reasonably longstanding relationship with Mr Dickey which, from the tone of their communications, verged on a friendship. Moreover, having regard to the approach taken by Mr Dickey in the strategy letter, which was communicated at least to Mr Holland, the experts were encouraged to see themselves as part of a team that was put together to rebuff the case that would be mounted by the Secretary and to ensure that the compensation awarded reflected the unique qualities of the land.
However, there is no evidence that the witnesses agreed – tacitly or otherwise – to the suppression of a supposedly final report and its replacement by a different document. Although Mr Holland provided a signed copy of a report in 2010, he gave evidence that his signature was automatically generated, and that the report was not intended to be a final report.
Furthermore, the evidence that changes were made to drafts of Mr Murray’s or Mr Holland’s expert reports as a result of review by Mr Dickey or Murdesk’s lawyers was limited. For the reasons I have previously stated, it was not sufficient to persuade me that the opinions expressed in the reports were not based on the specialised knowledge of the experts. In this case, Mr Dickey’s involvement in the formation of expert opinion, while in many respects concerning, did not amount to the kind of interference that was evident in [Phosphate Cooperative Co of Australia Pty Ltd v Shears [1989] VR 665].

At [63 – 65] of the ruling, Emerton J said:
This history shows that Mr Holland had relatively frequent contact with Mr Dickey … Many of the interactions were benign, in that they involved requests for and the provision of information. There was nothing unusual or untoward in Mr Dickey furnishing Mr Holland with information that might be useful for his valuation. To the extent that some of the communications involved Mr Dickey explaining what he saw to be the advantages of the subject land and describing his plans for it that too is innocuous. Communications of both kinds are an incident of the valuation process and do not in themselves compromise the independence of the valuer.
However, the communications … went further than this. Mr Holland repeatedly referred parts of his draft report to Mr Dickey for Mr Dickey’s ‘input and guidance’ and for ‘feedback’ (and ‘further feedback’). In the period during which he was finalising his report, Mr Holland’s revisions were sent systematically to Mr Dickey for his ‘review’.
… some of the language used by Mr Holland in his dealings with Mr Dickey is suggestive of a collaboration, … to maximise the value attributed to the land. References to ‘our cause’, to ‘heading off [opposing arguments] at the pass’, to achieving an ‘optimum level of value’ and so on, suggest that Mr Holland saw his task as one of advancing the interests of Murdesk in the compensation proceedings. Mr Dickey … wrote of providing the experts with ‘ammunition’ to defend ‘our’ claim. Mr Holland responded in kind by referring to his task as the ‘arguing up’ of value and, among other things, the need to find a demonstrable basis for an increase in the per square metre value of the land over the values of the surrounding land.
But at [282] of the judgment, her Honour added:
Although I found in my earlier ruling that many of the interactions were benign or innocuous, there were many that were inconsistent with an independent valuation process.
At [261] of the judgment, Emerton J said:
… this course of dealing severely compromised Mr Holland’s independence and must affect the weight that the Court can give to his opinion as to the value of the subject land. …

MR HARTLEY’S EVIDENCE

As indicated, I prefer Hartley’s opinion in relation to the causes of the tree falling.
His opinion was that the decay (white rot) on the tree’s woody roots had a significant impact on the tree’s failure; the tree had lost much of its structural support over a number of years; Contek (through the construction works) did not introduce the fungus to the tree causing the white rot; the decay in the tree had been present for about a decade or so; the removal of soil in the tree’s TPZ has not directly contributed to the failure of the tree; and the roots which appeared to have been severed (as noted in the tree inspection report) did not in any event contribute to the failure of the tree.
There is no issue with Hartley’s independence.
His evidence is consistent with the tree inspection report, in which Delaney made observations with the benefit of actually seeing the tree two and a half months after the storm.
Hartley took into account the effect on the tree’s stability of the two large structural roots that Delaney mentioned as appearing to possibly have been severed. He said he did not take into account the roots that would have been cut through in the removal of topsoil or other work on the site.
He gave an explanation in relation to this, during cross examination:
Now, if there were the removal of topsoil or a site cut within the TPZ of tree 25, that would have cut roots of tree 25 as well, wouldn’t it?---Yes. So we need to define our terms. There are different sorts of roots. There are structural roots. Those are roots that are often rapidly tapering, have an altered morphology in cross-section. If you cut it like a carrot, they'd not be round in shape; they'd be abnormally shaped or rapidly tapering. Then there's woody roots, and they're just ordinary roots that have got wood in them. They're older and they're about transport. And then finally we've got absorbing roots, and absorbing roots aren't woody. And a tree of the size that we're talking about would have potentially had hundreds of thousands, if not millions, of absorbing roots. So when we're talking about the cutting of the roots, the two roots that we're talking about are large woody roots that were potentially offering some structural support, not absorbing roots or small woody roots.
Hartley did not agree with Nicolle that if a root is damaged or cut, the whole root is impacted over time. He said:
…a root has got lots of live tissue. It's like cutting a branch, and we've all seen branches that have been cut off, they can happily grow back and flourish, they develop new tips. So cutting a root doesn't necessarily result in the death of the root, it just results in the death of the margin at that cut end.
He was asked:
So it's your evidence that you might cut or damage a root and you are not going to see an impact along the whole of the root. Is that your evidence?
He responded:
I would hope so. I transplant large trees worldwide. To date, there are about 45 or 46 thousand trees that we've been involved in transplanting and you don't get a whole pile of decay going right back through the root system and causing the death of the tree or causing structural disability. In fact, our very earliest well-recorded transplants that are still running were transplanted by Sir Henry Stuart in the early 1800s and many of those trees are still standing. In fact, here at Melbourne Botanic Gardens, Guilfoyle moved quite a number of trees in the 1880s and most of those trees are still standing. So cutting of the roots doesn't result in a massive influx of decay. Trees are (indistinct) they can't move, and because they can't move they have to have very good defence systems. Trees have diffuse organs, that is, they don't have everything concentrated in one spot. We lose our head, we die. We lose our kidney, we die. In a tree, if it loses a part, it adapts, and that's why they're able to survive for just not short periods of time, but for centuries and thousands of years in some instances.
Hartley was then asked if transplanting trees is obviously a different scenario than the one in question which considered the impact of site works on a tree that remains in situ. His answer was:
It’s identical…When you're cutting roots and, in fact, it's worse when you're transplanting because when you're transplanting you're cutting roots on all sides of the tree and underneath the tree. So it's about the worst form of stress that you can put onto a tree.
He was then asked:
But you'd accept we're talking about different scenarios, one is moving a tree, ideally under the care of an arborist to a different location, and the issue we're looking at here is what the impact of site works was where the tree remained in place
He responded:
We're talking in both cases about the impact of root cutting on the organ - on an organism. So root cutting on the tree or root cutting on the tree and the extent of root cutting on the tree in both instances, and when it comes to transplanting, the extent of root cutting is significantly greater than what we're talking about in most development sites.
His report referred to the fact that the root did not fail at the line of excavation. He was asked about this:
It is an oversimplification to say "Well, if the root didn't fail at the line of excavation, it couldn't have been the excavation that caused the tree to fail"?
He answered:
No, I don't think that's an oversimplification…I think that's a pretty obvious situation that if something is rotated, it rotates along the weakest line and there wouldn't have been substantial change in this instance in the 18 months between the strength of the root prior and to any works starting and the time of the failure.
Hartley agreed that you need to look at all of the works that occurred on the site, not just the cutting of structural roots to determine the impact on the tree’s structural health.
It was put to him in cross-examination that he looked at the failure to protect the TPZ and the cutting of the roots in the SRZ in isolation and did not assess all the factors together. His answer was blunt:
You can stand corrected, I’ve considered the whole impact, this is not much different from any other construction site that generally takes place within Australia.
He agreed that the removal of topsoil is not ideal in terms of tree health, and that there is some impact on its health. He went on to compare it to the process that occurs when a tree is transplanted:
Well the removal of soil results in the removal of some of those smaller woody roots and a large number of the absorbing roots, which means the tree is then dependent on the remaining root system to perform those tasks and that’s exactly the same process by the way that occurs when we transplant a tree. We take off 90 per cent or so of those woody and absorbing roots that are on the tree and then work with the remaining root system to make it function.

CONCLUSION

The plaintiffs have not established their claim. I will dismiss it.
I direct the parties to consider the orders that should be made as a result of these reasons – including as to costs. If the proposed orders are not agreed, submissions as to the proposed orders should also be provided by each party. If a hearing is required on these matters, it will then be listed.

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Certificate

I certify that these 67 pages are a true copy of the reasons for decision of her Honour Judge Marks, delivered on 22 March 2019, and revised on 26 March 2019.

Dated: 26 March 2019
Zeinab Ali

Associate to Her Honour Judge Marks