EML as agent for Insurance for NSW v AAI Limited t/as GIO - [2019] NSWWCCPD 60

DETERMINATION OF APPEAL AGAINST A DECISION OF THE COMMISSION CONSTITUTED BY AN ARBITRATOR
CITATION:	EML as agent for Insurance for NSW v AAI Limited t/as GIO [2019] NSWWCCPD 60
APPELLANT:	EML as agent for Insurance for NSW
RESPONDENT:	AAI Limited t/as GIO
INSURER:	Not applicable
FILE NUMBER:	A1-5654/18
ARBITRATOR:	Mr J Wynyard
DATE OF ARBITRATOR’S DECISION:	3 June 2019
DATE OF APPEAL DECISION:	3 December 2019
SUBJECT MATTER OF DECISION:	Sections 22 and 22A of the Workers Compensation Act 1987 (the 1987 Act) – apportionment of liability for weekly payments between insurers – whether an Arbitrator is bound by earlier agreed apportionment in respect of treatment expenses pursuant to s 60 of the 1987 Act and entitlements pursuant to s 66 of the 1987 Act; adequacy of reasons – Precision Valve Australia Pty Ltd v Nanda [2012] NSWWCCPD 48 discussed; Beale v Government Insurance Office (NSW) (1997) 48 NSWLR 430, Woolworths Ltd v Warfe [2013] VSCA 22 applied; whether the decision is illogical or irrational – Minister for Immigration and Citizenship v SZMDS [2010] HCA 16; 240 CLR 611; 84 ALJR 369; 266 ALR 367 applied
PRESIDENTIAL MEMBER:	Deputy President Elizabeth Wood
HEARING:	On the papers
REPRESENTATION:	Appellant:
Mr D Baran, counsel
Rankin Ellison Lawyers
Respondent:
Mr D Priestley SC, counsel
Thompson Cooper Lawyers
ORDERS MADE ON APPEAL:	1. The Amended Certificate of Determination dated 3 June 2019 is confirmed. 2. The appellant is to pay the respondent’s costs of this appeal.

INTRODUCTION

This appeal concerns an application made by EML as agent for Insurance for NSW (the appellant) for apportionment of liability for payments of weekly compensation and treatment expenses made to Mr Stephen Bearman (the worker). The appellant sought the apportionment between it and AAI Ltd t/as GIO (the respondent) pursuant to ss 22 and 22A of the Workers Compensation Act 1987 (the 1987 Act).
The Arbitrator determined that the weekly payments were to be apportioned on the basis of 75 percent to the appellant and 25 percent to the respondent. The Arbitrator further determined that the treatment expenses pursuant to s 60 of the 1987 Act were to be apportioned as 25 percent to the appellant and 75 percent to the respondent.
The appellant appeals the Arbitrator’s decision.

BACKGROUND

The worker was employed by Fire and Rescue NSW as a fire fighter from approximately 1984. In or about October or November 1988, the worker suffered an injury to his back when he stepped out of his vehicle while carrying a large pot of curry prepared for his colleagues at the station and lost balance, twisting his back (the 1988 injury). The worker was hospitalised for six weeks, during which time he underwent a laminectomy and discectomy at the hands of Dr Anthony Hodgkinson, orthopaedic surgeon. He remained off work for approximately six months, returned to modified duties for a further six months and then returned to his pre-injury duties.
In July 2007, the worker suffered a further injury to his back when he slipped on an icy road surface while alighting from the brigade vehicle (the 2007 injury). The worker thereafter was unable to return to his usual duties. In 2013, the worker underwent further surgery in the form of a spinal fusion, this time at the hands of Associate Professor Brian Owler, neurosurgeon.
The evidence points to various other incidents relating to back pain, both before and after the 1988 injury.
The respondent was the insurer on risk for all periods up to 30 June 1989 and from 1 July 1989 the insurer on risk was the appellant.
In 2008, the appellant and the worker entered into a complying agreement in accordance with s 66A of the 1987 Act in respect of 2% whole person impairment pursuant to s 66 of the 1987 Act as a result of the 2007 injury. At about the same time, the respondent and the worker also entered into a complying agreement in respect of the permanent impairment of the worker’s back and the loss of efficient use of the worker’s right and left lower extremities.

ON THE PAPERS

Section 354(6) of the Workplace Injury Management and Workers Compensation Act 1998 (the 1998 Act) provides:
“(6) If the Commission is satisfied that sufficient information has been supplied to it in connection with proceedings, the Commission may exercise functions under this Act without holding any conference or formal hearing.”
Both parties are content for the appeal to be determined on the papers.
I have had regard to Practice Directions Nos 1 and 6; the documents that are before me, and the submissions by the parties that the appeal can proceed to be determined on the basis of these documents. I am satisfied that I have sufficient information to proceed ‘on the papers’ without holding any conference or formal hearing and that this is the appropriate course in the circumstances.

THRESHOLD MATTERS

There is no dispute between the parties that the threshold requirements as to quantum and time pursuant to ss 352(3) and 352(4) of the 1998 Act have been met.

THE EVIDENCE

The medical evidence

Various medical experts provided opinions on causation and apportioned liability between the two significant injuries.

Dr John Bentivoglio, orthopaedic surgeon

Dr John Bentivoglio was qualified by the worker’s legal representatives to provide an assessment of the worker’s permanent impairment for the purpose of a claim for lump sums pursuant to s 66 of the 1987 Act. He provided a report dated 30 July 2008.[1]
[1] Miscellaneous Application (Application), pp 121–129.
Dr Bentivoglio noted the injury to the back occurring in July 2007 when the worker slipped on ice. He also took a history of the earlier injury in 1988 and the presence of significant symptoms in the back together with pain radiating down the right leg following that injury. Dr Bentivoglio further noted that following the laminectomy performed by Dr Hodgkinson and after time off work, the worker’s symptoms improved to an acceptable level and the worker was able to tolerate pre-injury duties.
Dr Bentivoglio recorded the history of three or four further significant episodes of back pain which settled within three or four weeks following conservative treatment. Dr Bentivoglio also took the history that, following the 2007 injury, the worker was unable to return to work and was medically retired in 2008.
Dr Bentivoglio reviewed the radiological investigations and examined the worker. He was of the opinion that the 1988 injury caused probable disc damage. He noted that the flare-ups of back pain all settled to an acceptable level, until the 2007 injury, which caused significant symptoms in the back that never settled. Dr Bentivoglio predicted that the worker’s degenerative condition in the lumbar spine might worsen and could have worsening spinal canal stenosis that may require surgery in the future.
Dr Bentivoglio assessed the worker’s permanent impairment of the back as 40% impairment, three quarters of which was attributable to the 1988 injury and one quarter to the 2007 injury. He also assessed the worker as having a 15% loss of efficient use of his right lower extremity and 10% loss of efficient use of his left lower extremity. Dr Bentivoglio attributed the following losses to the 2007 injury:
(a)    10% permanent impairment of the back;
(b)    10% loss of efficient use of the left lower extremity, and
(c)    5% loss of efficient use of the left [sic, right] lower extremity.
In a supplementary report dated 30 July 2008, Dr Bentivoglio assessed the worker’s whole person impairment (WPI) resulting from all injuries as 12%, of which 2% WPI resulted from the 2007 injury.[2] In a further report dated 4 September 2008, Dr Bentivoglio opined that the remaining 10% WPI was attributable to the 1988 injury and allowed a further 2% WPI because of the surgery, making a total of 12% WPI attributable to the 1988 injury.[3]
[2] Application, pp 130–131.
[3] Application, pp 132–133.

Dr Roger Pillemer, orthopaedic surgeon

Dr Roger Pillemer provided a number of reports directed to the respondent’s legal representatives.
In his first report, dated 19 February 2009,[4] Dr Pillemer took a consistent history of the injury in 1988 and treatment that followed, the subsequent intermittent back problems causing brief periods off work and the 2007 injury, following which the worker was unable to return to work. Dr Pillemer reviewed the radiological investigations and concluded that a CT scan dated 28 November 1988 showed a significant disc protrusion at the L4/5 level, as well as some protrusion at the lumbosacral level, associated with calcification. He confirmed a further CT Scan dated 20 September 2007 showed moderate canal and lateral recess stenosis at the L5/S1 level suggestive of compression of the right S1 nerve root, and possible involvement of the left S1 nerve root. Dr Pillemer reported that an MRI scan dated 2 November 2007 confirmed degenerative changes at the lower two levels of the spine, some disc protrusion at the lumbosacral level with an annular tear and fissure. There was a suggestion of possible involvement of the S1 nerve roots.
[4] Application, pp 139–143.
Dr Pillemer diagnosed a significant disc protrusion at the L4/5 level caused by the 1988 injury. He attributed the worker’s ongoing symptoms to the 1988 injury and the nature and conditions of the worker’s employment since that time.
In a separate report of the same date,[5] Dr Pillemer assessed the worker’s WPI as 13%. Dr Pillemer apportioned 2% WPI to the work performed by the worker after 1 January 2002, including the injury in July 2007. Dr Pillemer concluded that the most significant cause of the worker’s incapacity was the injury in 1988.
[5] Application, pp 144–146.
In a third report dated 2 October 2018,[6] Dr Pillemer noted that Dr Michael Davies, an approved Medical Specialist (AMS) had apportioned 75% of the liability to the respondent in respect of the 1988 injury and 25% to the appellant in respect of the 2007 injury. Dr Pillemer referred to his earlier report in which he had assessed 13% WPI, of which 11% WPI was attributable to injuries prior to 2002 and 2% WPI was attributable to injuries from 1 January 2002. Dr Pillemer noted that the AMS had apportioned the impairment between the 1988 injury and the 2007 injury and expressed the view that his apportionment would be the same as he had already assessed.
[6] Application, pp 147–148.

Dr Vidyasagar Casikar, consultant neurosurgeon

Dr Vidyasagar Casikar provided a report dated 3 March 2012, directed to the appellant.[7]
[7] Application, pp 194–202.
Dr Casikar took a history of both the 1988 and the 2007 injuries and reviewed an MRI scan dated 29 March 2011. He noted the worker had done well following the surgery performed by Dr Hodgkinson. Dr Casikar was of the opinion that the worker had significant degenerative changes in the lumbar spine which had probably increased and suffered from persistent back pain. Dr Casikar formed the view that the worker’s condition was predominantly due to degenerative lumbar disease, the 2007 injury was an aggravation of that condition but the aggravation had ceased. Further, the worker had recovered completely from the surgery in 1988. Dr Casikar did not recommend further surgery.

Dr Michael Davies, AMS

Dr Michael Davies was requested to provide a non-binding medical opinion as to whether the worker’s pathology and symptoms resulted from the 1988 injury, or the 2007 injury, or a combination of both. He was also asked to opine whether the spinal fusion surgery proposed by A/Prof Brian Owler was reasonably necessary as a result of the 1988 injury, the 2007 injury, or both injuries. Dr Davies performed an assessment of the worker and provided a Medical Assessment Certificate dated 22 March 2013.[8]
[8] Application, pp 238–249.
Dr Davies took a consistent history of the injuries in 1988 and 2007, but also noted other incidents in the course of the worker’s employment, both before and after the 1988 injury. Dr Davies noted that the worker described the 1988 and 2007 injuries as the most significant events. Dr Davies reviewed the radiological evidence and detailed the level of symptoms that presented over the years. He concluded that the main contributing factor to the worker’s condition was the 1988 injury, and that a further incident in 1992 (which was less significant) and the significant incident in 2007 were aggravations of the 1988 injury.
Dr Davies confirmed that the worker’s condition related to both the 1988 injury and the 2007 injury, but that the 1988 injury was predominant. Dr Davies was of the opinion that the surgery was reasonably necessary as a result of both injuries. Given the history of complaints of pain and the treatment offered, it was appropriate to apportion 75% of the liability for the surgery to the respondent and 25% to the appellant.

Associate Professor Brian Owler, neurosurgeon

The worker was referred to A/Prof Brian Owler by his general practitioner, Dr Avi Kanetkar in March 2011. A/Prof Owler provided a number of medical reports directed to the general practitioner and to the appellant, as well as the respondent.
In a report dated 14 February 2017 directed to the appellant’s legal representatives,[9] A/Prof Owler indicated that, after reviewing the material provided to him, he agreed with the apportionment as expressed by Dr Davies, that is that 75% of the liability was due to the 1988 injury and 25% to the 2007 injury. He reasoned that:
(a)    the long-term consequences of the 1988 injury were likely to be more significant;
(b)    there was a prolonged hospitalisation and extended recovery period following that injury;
(c)    a laminectomy and discectomy were required;
(d)    the 1988 injury likely contributed to accelerated changes and degeneration of the L5/S1 disc, and
(e)    because the 2007 injury appeared to have affected the L5/S1 disc (which was below the level of the 1988 surgery), it was a significant injury and should be afforded some liability.
[9] Application, pp 178–179.

The documentary evidence

The appellant, respondent and the worker entered into complying agreements pursuant to s 66A of the 1987 Act and consent orders in respect of the worker’s entitlements pursuant to s 66 and in respect of the surgery proposed by A/Prof Owler. Those were:
(a)    a Certificate of Determination (COD) recording Consent Orders dated 11 June 2013. That document recorded that the parties agreed that the proposed surgery was reasonably necessary, and that the liability for the surgery was to be apportioned as 75% to the respondent and 25% to the appellant;[10]
(b)    a complying agreement dated 8 July 2009 entered into by the worker and the appellant, agreeing to resolve the WPI of the worker’s back resulting from the 2007 injury for 2% WPI,[11] and
(c)    a complying agreement entered into by the worker and the respondent dated 9 July 2009. That document recorded an agreement that the worker suffered 18% permanent impairment of the back, 5% of the right leg at and above the knee and 2% of the left leg at and above the knee as a result of the “nature and conditions of employment from 30 June 1973 to 30 June 1989.”[12]
[10] Application, p 249.
[11] Application, pp 345–347.
[12] Application, pp 348–350.

THE ARBITRATOR’S REASONS

The Arbitrator identified the issues to be determined as:
(a) whether an order for apportionment should be made, and
(b) if so, what was the just and equitable apportionment in the circumstances of the case.
The Arbitrator summarised the history of the worker’s employment. He described the manner in which the 1988 injury occurred, and the treatment provided by Dr Hodgkinson.
The Arbitrator referred to the history provided to Dr Davies, AMS, of an injury in 1992. The Arbitrator pointed to evidence annexed to the Reply to the application, which established that the injury actually occurred on 12 December 1991. The evidence also showed that the worker was hospitalised in Ryde Hospital and subsequently transferred to the Sydney Adventist Hospital, and was discharged on Christmas Eve.
The Arbitrator referred to a faded medical certificate dated 8 June 1993 which referred to the onset of sciatica and certified the worker as unfit for work for seven days. The Arbitrator noted a further injury in 1996.
The Arbitrator also noted that the worker ceased operational duties in 1997 and became a trainer (although was required to perform operational duties from time to time) and, after further study, became a Duty Commander.
The Arbitrator further described the mechanism of the 2007 injury and the onset of increased pain with a “popping” feeling in the low back. He noted the treatment regime included bed rest for two to three weeks before attempting to mobilise and the surgery performed by A/Prof Owler on 5 August 2013.
The Arbitrator summarised the medical opinions of Dr Davies, Dr Bentivoglio, Dr Pillemer, A/Prof Owler and Dr Casikar.
The Arbitrator recorded an overview of the submissions from both parties and quoted from ss 22 and 22A of the 1987 Act as well as from Part 5 of the application, which detailed the orders sought by the appellant. The orders sought were that the payments the appellant had made should be apportioned between the appellant and the respondent on the basis of 25% to the appellant and 75% to the respondent.
The Arbitrator commented that he was not appraised of the payment made by the appellant, and that the respondent’s defence was only directed to the question of weekly payments. The Arbitrator inferred therefore that the dispute before him related to the question of “economic incapacity.”[13]
[13] Employers Mutual NSW Limited v AAI Limited [2019] NSWWCC 183 (reasons), [75].
The Arbitrator expressed the view that, in respect of the lump sum entitlements pursuant to s 66 and the treatment expenses pursuant to s 60, as far the question of causation was concerned, he preferred the opinion of Dr Davies that liability should be apportioned as 75% to 25%. He noted that opinion was supported by all of the medical experts except for Dr Casikar. The Arbitrator said, however, that the question of liability for weekly payments falls under a different category. The Arbitrator referred to the heading of Division 2 of Part 3 of the 1987 Act, which is entitled “Weekly Compensation by way of Income support”. The Arbitrator considered therefore that the weekly compensation category “is defined not by causation, but by the effect a given injury has on the worker’s capacity to earn.”[14]
[14] Reasons, [77].
The Arbitrator considered the heading and contents of s 33 of the 1987 Act, noting that the heading referred to partial and total incapacity, which were undefined terms. The Arbitrator made the following observation:
“‘Total’ or ‘partial’ incapacity are not defined under the Act. Section 32A speaks in terms of ‘current work capacity’ or ‘no current work capacity’ to define the same concepts, with the definition of a current work capacity being dependent upon an injured worker’s ability to return to work in suitable duties. It is not necessary to define the concept of weekly compensation further, as it is concerned with complex equations and different periods of entitlement. It is apparent however that liability to pay weekly compensation by an employer is dependent upon the effect of a worker’s injury on his capacity to earn. As such, it is not dependent upon any finding as to the cause of his injury.”
The Arbitrator considered that there was no evidence that the 1988 injury caused anything but temporary occasional aggravations between that injury and the 2007 injury, which was a period of 19 years. He referred to a submission made by the appellant that the distinction between apportionment in respect of treatment expenses and an apportionment in respect of weekly payments was a “distinction without a difference.” The Arbitrator rejected that submission because, he said, s 22(1)(c) and s 22A(1)(b) gives the Commission a discretion in relation to apportionment, which is to be exercised in a “just and equitable manner” according to the special circumstances of the case. The Arbitrator remarked that the discretion must be exercised in accordance with the law, so that in the apportionment of weekly payments, regard must be had to the evidence relating to the injured worker’s capacity to earn.

The Arbitrator rejected the opinion of Dr Casikar as it was unsupported by any other medical opinion, barring that the degenerative changes played a role in the subsequent aggravations. The Arbitrator accepted the opinion of A/Prof Owler that the intensive surgical treatment of the 1988 injury may have contributed to and accelerated the degenerative changes of the L5/S1 disc. The Arbitrator said that A/Prof Owler’s opinion was supported by that of Dr Davies, who was of the view that the 1988 injury set in train an acceleration of degeneration of the lumbar spine, evidenced by the subsequent “flare ups” of back pain from then until 2007.
The Arbitrator observed that there was no evidence that the worker’s change of duties in 1997 was referrable to any disability caused by the 1988 injury. The change of duties appeared to be a promotion, and in the Arbitrator’s view, the worker continued at times to perform operational duties which indicated he had an ability to do full duties.
The Arbitrator said that he took into account that between 1988 and 2007, the worker from time to time suffered work related aggravations of his lumbar spine, some of which were more serious than others. The Arbitrator considered that nonetheless, the 1988 injury was responsible for those periods of incapacity and found that some apportionment should be made for the payment of weekly compensation.
The Arbitrator referred to the method of apportionment provided for in s 22A(1)(b) and considered that he should not make an order of apportionment based on the relative lengths of the periods each insurer was on risk. The Arbitrator noted that he had the power to make an order on a different basis if there were special circumstances that made it just and equitable to do so. The Arbitrator identified the special circumstances in this case to be the generality of the evidence in relation to the occasional aggravations. He was satisfied that the worker’s back symptoms were minor irritations that flared up from time to time during the worker’s career.
The Arbitrator determined that payments made for and on behalf of the worker in respect of weekly payments of compensation should be apportioned on the basis of 75% to the appellant and 25% to the respondent. The Arbitrator stressed that the apportionment did not apply to the worker’s lump sum entitlements or treatment expenses. In respect of those entitlements, he felt the apportionment suggested by the AMS was appropriate and he found accordingly.
The amended Certificate of Determination (COD) (which corrected a typographical error in the initial COD) issued on 3 June 2019 records:
“The Commission determines:
1.     Payments of weekly compensation made to, for and on behalf of Mr Stephen Bearman as a result of his injury sustained on 17 July 2007 should be apportioned between EML and GIO on the following basis:
a.75% to EML
b.25% to GIO
2.    Payments of lump sum and/or s 60 compensation made to, for and on behalf of Mr Bearman as a result of his injury of 17 July 2007 should be apportioned between EML and GIO on the following basis:
a.25% to EML
b.75% to GIO
3.    Liberty to apply.”

GROUNDS OF APPEAL

The appellant brings the following grounds of appeal:
(a)    Ground one: The Arbitrator erred in determining that a claim for apportionment in respect of weekly payments of compensation should be treated differently to a claim in respect of medical expenses.
(b)    Ground two: The Arbitrator failed to give adequate reasons for his determination of the apportionment, thereby denying the appellant procedural fairness.
(c)    Ground three: The Arbitrator’s determination was either not supported by any evidence or was illogical and irrational, so that the Arbitrator committed a jurisdictional error.

LEGISLATION

Section 22 of the 1987 Act relevantly provides:
“22    Compensation to be apportioned where more than one injury
(1)     If—
(a)the death or incapacity of a worker, or
(b)a permanent impairment suffered by a worker as referred to in Division 4 of Part 3, or
(c)a liability under Division 3 of Part 3 to a worker,
results from more than one injury to the worker, liability to pay compensation under this Act is to be apportioned in such manner as the Commission determines.
(1A) …
(2)     Liability to pay compensation under this Act includes—
(a)the liability of an employer (including an employer who is a self-insurer), and
(b)the liability of an insurer under a policy of insurance in respect of the payment of that compensation (including a direct liability to the worker), and
(c)a liability in respect of a claim under Division 6 of Part 4, and
(d)in the case of a worker who is partially incapacitated for work, a liability that arises because the worker is entitled to be compensated under this Act as if totally incapacitated.
(3)     Liability to pay compensation under this Act is not to be apportioned by the Commission if the parties to whom the liability relates have agreed on the apportionment.
(4)     …
(5)     The Commission may, on the application of any insurer or employer concerned or of the Authority, determine a dispute as to whether—
(a)liability to pay compensation under this Act should be apportioned under this section, or
(b)any such liability should be apportioned under this section in respect of different injuries.
The determination of the Commission has effect despite any agreement on apportionment if the application for determination was made by an employer (in the employer’s own right) or the Authority.
...
(7)     A person who is liable to pay compensation under this Act is not entitled in any proceedings under this Act to a reduction in that liability by apportionment on account of the existence of any other person who is also liable to pay any part of that compensation unless that other person is a party to the proceedings.
(8)     This section applies to any liability arising before or after the commencement of this Act”.
Section 22A of the 1987 Act relevantly provides:
“22A Further provisions concerning apportionment of liability under section 22
(1)     The apportionment of liability under section 22 is—
(a)in the case of the apportionment of liability between employers—to be on the basis of the relative length of the worker’s employment with each employer concerned (not including any period of employment after the last relevant injury was received), or on such other basis as the Commission considers just and equitable in the special circumstances of the case, and
(b)in the case of the apportionment of liability between insurers of the same employer—to be on the basis of the relative length of the employer’s period of insurance with each insurer concerned during which the worker concerned was employed by the employer (not including any period of insurance after the last relevant injury was received), or on such other basis as the Commission considers just and equitable in the special circumstances of the case.
…
(3)     Liability may be apportioned under section 22 even if the liability has been discharged.
(4)     When liability to pay compensation is apportioned under section 22 between 2 or more persons, the Commission may order that the compensation is payable to the worker by one of those persons and that the other persons are to pay (by way of contribution) their apportioned share of that compensation to that person.
(5)     The person ordered under subsection (4) to pay compensation to the worker is to be—
(a)in the case of apportionment between employers—the employer who most recently employed the worker, or such other of the employers as the Commission considers reasonable in the special circumstances of the case, and
(b)in the case of apportionment between insurers—the insurer of the employer at the time of the last injury, or such other of the insurers as the Commission considers reasonable in the special circumstances of the case.
(6)     An order is not to be made under subsection (4) if the parties concerned have agreed as to the payment by one of them of the compensation concerned.
(7)     In this section a reference to an insurer includes a reference to a self-insurer and a reference to a period of insurance includes a reference to a period of self-insurance. A liability in respect of a claim under Division 6 of Part 4 is for the purposes of this section taken to be a liability of the insurer of the employer concerned during the period that is relevant to that liability.
(8)     In a case to which section 22 applies, if all of the insurers concerned (being either insurers of the same employer or of the different employers concerned) are insurers within the meaning of Division 4 of Part 7 and the entitlement of the worker (or other claimant) to receive compensation is not disputed—
(a)the compensation is (despite subsection (5)) payable by the last insurer or the last employer (as relevant to the case), with no apportionment of liability under section 22, and
(b)for the purposes of calculating an insurance premium payable by any of those employers, their claims histories are to be determined on the assumption that liability had been apportioned under section 22 (without the need for a determination of, or agreement as to, that apportionment).
(9)     The operation of section 22 is not to be limited because of the fact that it provides for liability to be apportioned rather than providing for payment of contributions.”

SUBMISSIONS

The appellant’s submissions

The appellant generally submits that Dr Bentivoglio, Dr Pillemer and Dr Davies all agreed that the 1988 injury was responsible for a substantial proportion of the damage done to the worker’s spine up to the exacerbation of the worker’s symptoms in the 2007 injury. The appellant says that there is no issue that the worker was totally incapacitated for work as a result of the back injuries and he was, accordingly, being paid weekly compensation.
The appellant further says that the respondent did not arrange for the worker to be medically examined for the purpose of these proceedings and did not rely on any new or additional evidence to contradict the evidence of Dr Bentivoglio, Dr Pillemer, A/Prof Owler or Dr Davies.

As to ground one – alleged error by apportioning the weekly payments differently to the medical treatment

The appellant refers to the Arbitrator’s observations quoted at [43] above, in which the Arbitrator regarded that the liability for weekly payments could be distinguished from the liability for treatment expenses or lump sums because weekly compensation is “defined not by causation but by the effect a given injury has on an injured worker’s capacity to earn.” The appellant contends that the Arbitrator erred because these proceedings were seeking apportionment, and not a determination of a primary liability to pay weekly compensation. The only issue for the Arbitrator to determine was the apportionment of that liability.
The appellant submits that the correct approach in determining apportionment requires a direct inquiry into causation. The appellant relies on Rail Services Australia v Dimovski,[15] New South Wales Police Force v Kearns[16] and Kooragang Cement Pty Ltd v Bates[17] as authorities for that proposition.
[15] [2004] NSWCA 267; 1 DDCR 648.
[16] [2008] NSWWCCPD 29, [61].
[17] (1994) 35 NSWLR 452; 10 NSWCCR 796 (Kooragang).
The appellant asserts that there is no distinction between the type of compensation that is to be apportioned. The appellant quotes from Ferndale Partnership v Widdison,[18] in which Acting Deputy President Handley adopted the same apportionment in a claim for weekly payments as the AMS had apportioned the lump sum claim.
[18] [2006] NSWWCCPD 261 (Widdison), [34].
The appellant concludes that, when undertaking the statutory exercise as to what is just and equitable, the particular head of compensation is irrelevant because the Commission is undertaking a very different inquiry to one of determining a dispute about primary liability. The appellant says that, on that basis, the Arbitrator committed an error of law.

As to ground two – alleged failure to give adequate reasons resulting in procedural unfairness

The appellant submits that the Arbitrator, in the exercise of his discretion, was duty bound to provide adequate reasons as to why he rejected the opinions of Dr Davies, A/Prof Owler, Dr Bentivoglio, who had all apportioned three quarters of the worker’s condition to the 1988 injury. The appellant says that the Arbitrator was duty bound to provide proper reasons for departing from that unchallenged evidence and preferring other evidence. The appellant asserts that this is particularly so when the respondent expressly relied upon those opinions when it conceded that it was liable for 75% of the cost of the surgery in 2013. The appellant contends that, given that those opinions were unchallenged by contrary medical evidence to the extent that they were shown to be wrong, the Arbitrator required a sound basis upon which to reject them.
The appellant submits that, in the context of no conflicting evidence, the Arbitrator was duty bound to provide reasons as to his preference for one version over the other, and he failed to do so, thus not discharging his function.
The appellant refers to the Arbitrator’s observation that there was no evidence the 1988 injury caused anything other than temporary aggravations over the period 1988 to 2007 and submits that this is not “the test”. The appellant says that the evidence shows that by the time the worker was permanently unfit for duty, he was suffering from a back condition on account of both accidents, that resulted in a significant proportion of the instability being caused by the 1988 injury. The appellant asserts that it was the severity of the 1988 injury that set the scene for the inability to work and the need for the further surgery. The appellant says that the Arbitrator seems to have ignored the severity of the 1988 injury in the context of the worker having to undergo the initial surgery and the fact that the 1988 injury destabilised the worker’s lumbar spine.
The appellant points out that the Arbitrator accepted the opinions of A/Prof Owler and Dr Davies, which was contrary to his ultimate determination and maintains that the ultimate decision was contrary to the evidence. The appellant submits that in the absence of adequate reasoning, a jurisdictional error has occurred, which entitles Presidential intervention.

As to ground three – whether the Arbitrator’s decision was supported by the evidence or was otherwise illogical or irrational

The appellant contends that the Arbitrator’s determinations in paragraphs one and two of the COD are irreconcilable and maintains that there was no evidence to support the finding that the appellant was liable for 75% of the weekly payments. The appellant submits that there was no finding of fact or any available inference that would justify a departure from the evidence and which the Arbitrator could rely upon, in special circumstances, to exercise his discretion as he did. The appellant contends that the authorities make it clear that such a departure is capable of grounding an error of law, in particular a jurisdictional error, which requires Presidential intervention. The appellant maintains that the error is the failure to properly decide, and the decision has been infected by an illogical and irrational process.

The respondent’s submissions

In general submissions, the respondent points to s 352 of the 1998 Act, which limits an appeal from an arbitrator’s decision to a determination as to whether the arbitrator’s decision was, or was not, affected by error of fact, law or discretion. The respondent says that the power is a narrow one and does not allow a general discretion to re-open or reconsider the Arbitrator’s decision. The respondent says that the appeal process is defined by the establishment and correction of error. It contends that the appellant must establish that the view taken by the Arbitrator of the primary facts found and any inferences drawn from those facts were not just different to those that might have been found by the appellate tribunal. It must be shown that they were wrong. The respondent cites authorities for those propositions.[19]
[19] Whiteley Muir and Zwanenberg Ltd v Kerr (1966) 39 ALJR 505 at 506; Zuvela v Cosmarnan Concrete Pty Ltd (1966) 140 ALR 227.
The respondent submits that what constitutes an error of the kind required will be determined on a case by case basis, guided by the principles in Fox v Percy.[20] Further, the Arbitrator’s reasons should be read as a whole, without combing them for error.

As to ground one – alleged error by apportioning the weekly payments differently to the medical treatment

[20] [2003] HCA 22; 214 CLR 118.

The respondent points out that the Arbitrator referred to and expressly approved the apportionment of the s 60 expenses. The respondent says that the apportionment of the s 60 expenses was consistent with the MAC issued by Dr Davies in relation to the liability for the surgery proposed by A/Prof Owler. Further, the parties agreed to that apportionment.
The respondent contends that the Arbitrator was correct in identifying the weekly payments as being of a different category because the liability to pay weekly payments is dependent upon the effect the injury had on the worker’s capacity to earn. The respondent asserts that the Arbitrator’s consideration does not purport to exclude as relevant the causes of the worker’s injury or condition in the apportionment of liability. The respondent says that the Arbitrator conducted an analysis of the evidence and the effects of the two injuries on the worker’s capacity to earn and submits that this was the correct approach. The respondent further says that the conclusion reached as to the apportionment was well open on the evidence.
The respondent submits that there is no constraint in the legislative provision to require the Arbitrator to find that the proportion of the liability for the weekly payments was identical to that of the apportionment in respect of the treatment expenses. The respondent further submits that there was nothing in terms of medical causation or otherwise that dictated that the Arbitrator needed to assess or apportion liability for weekly payments and treatment expenses on the same basis. The respondent contends that the apportionment of liability for the medical expenses had “plainly” been determined on the basis of the medical evidence as to the relative causes of the condition that requires the treatment. In contrast, it submits, the worker’s incapacity for work focused on the history of his ability to continue to work which, as the Arbitrator observed, involved lengthy periods of work as a fireman for many years leading up to the 2007 injury.
Also, the respondent says, there was medical evidence before the Arbitrator that showed that there was new pathology in the lumbar spine at the L5/S1 disc level, which the respondent contends was “not necessarily implicated in the 1988 injury”.[21] The respondent contends that this evidence alone was sufficient to justify the Arbitrator’s approach in treating the apportionment of liability for weekly payments differently to the liability for treatment expenses. The respondent concedes that the Arbitrator did not expressly rely upon that evidence but asserts that the Arbitrator made no error of fact, law, or discretion.
[21] Respondent’s submissions, [16].
The respondent contends that the authorities relating to causation relied on by the appellant do not dictate that the question of apportionment of liability for weekly payments and for treatment expenses cannot be treated differently. The respondent submits that the question is not “whether the form of the compensation is relevant to the causation enquiry, but whether the basis for liability for compensation can be separate and distinct”.[22] The respondent says that it plainly can.
[22] Respondent’s submissions, [17].

The respondent refers to Widdison and submits that the paragraph relied upon by the appellant is not authority for the proposition put forward by the appellant that no distinction is to be made in apportioning the weekly payments and the treatment expenses or lump sum entitlements. Rather, the respondent asserts, the Presidential member determined that in the circumstances of the case, it was not appropriate to assess the apportionment on a different basis to that of the lump sum entitlement. The respondent says that the Presidential member took into account the Arbitrator’s findings in relation to the physical capacity both before and after the later injury, which suggests that the Deputy President did not feel constrained to apply the same apportionment that applied to the permanent impairment entitlement.
The respondent submits that the history of the apportionment provisions discloses that difficulties have arisen in assessing whether, and in what circumstances, it can be said that incapacity for work arises out of more than one injury. The respondent refers to Morris v George,[23] where the Court of Appeal held that where a later injury imposed further disability upon the disability arising from earlier injuries, if the later injury caused the worker to cease work, then the later injury could be said to be the cause of the incapacity. The respondent observes that ss 22(1A) and 22A of the 1987 Act were expanded to allow for apportionment where the incapacity arose from separate injuries and refers to Sutherland Shire Council v Baltica General Insurance Co Ltd.[24]
[23] [1977] 2 NSWLR 552 (George).
[24] (1996) 39 NSWLR 87; 12 NSWCCR 716.
The respondent says that traditionally, it has been considered that a temporal connection between an injury and incapacity arising shortly thereafter is a strong indicator that one results from the other. The respondent maintains that where liability is to be fixed upon one injury alone, it will generally be the later injury, relying on Pickersgill v Freightbases Pty Ltd[25] as authority for that proposition.
[25] [1983] 3 NSWLR 117, 188G–119C.
The respondent further submits that ultimately, whether incapacity results from a work injury is a question of fact and it follows that whether incapacity and the need for treatment arise to the same extent is also a question of fact. It says that each case must turn on its own facts, and each case requires a common sense evaluation, as discussed in Kooragang.
The respondent concludes by submitting that the appellant has not pointed to any authority or statutory basis for the assertion that the approach taken by the Arbitrator was impermissible.

As to ground two – alleged failure to give adequate reasons resulting in procedural unfairness

The respondent submits that in any jurisdiction, the duty to give reasons is to be determined by the context, including the jurisdiction, and by having proper regard to the purposes for providing reasons, in accordance with the principles set out in Beale v Government Insurance Office (NSW).[26] In order to have the decision set aside, the respondent submits that the appellant must establish that the reasons are not only inadequate but that their inadequacy discloses a failure to exercise the statutory duty to determine the matter fairly and lawfully, relying on YG & GG v Minister for Community Services.[27]
[26] (1997) 48 NSWLR 430 (Beale).
[27] [2002] NSWCA 247.
The respondent contends that, in the present case, the Arbitrator extensively reviewed the relevant evidence and the parties’ submissions and gave reasons for coming to his conclusion as to the apportionment at [77]–[87] of his reasons. The respondent says that, having regard to the nature of the issue and the jurisdiction in which the issue was to be determined, it cannot be said that those reasons were inadequate.
The respondent submits that it is clear that in determining the relevant contributions of the injuries to the incapacity, the Arbitrator took into account the medical evidence “in a more general sense” and overlaid upon that evidence a consideration of the history of the worker’s incapacity.
The respondent asserts that the appellant has misapprehended the Arbitrator’s reasoning process. It contends that the Arbitrator took into account the opinions of Dr Davies, Dr Bentivoglio and A/Prof Owler to the extent that they apportioned the worker’s condition between the two injuries, but that is not all the Arbitrator did. The respondent says that there is nothing in the Arbitrator’s reasons that discloses that he failed to consider those opinions, which he in fact did, at length. Further, there is nothing to suggest that he rejected their opinions. The Arbitrator proceeded on the basis that the opinions were not expressly directed to the separate question of capacity to work, which the respondent says the appellant has acknowledged. The respondent maintains that the Arbitrator was entitled to consider other evidence, namely the worker’s work capacity history to determine the issue. The respondent says that the task was not one of resolving a conflict in the medical evidence. In any event, to the extent that there was any conflict, the Arbitrator addressed and resolved it.
The respondent submits that this is not a matter where the Arbitrator entirely ignored the severity of the 1988 injury, and points to the Arbitrator’s reasons where he expressly affirmed the 75% apportionment in respect of the liability for the treatment expenses. Further, the Arbitrator accepted that there was a 25% contribution from the 1988 injury to the incapacity after 2007, despite the many years that the worker continued to perform full duties after 1988.

As to ground three – whether the Arbitrator’s decision was supported by the evidence or was otherwise illogical or irrational

The respondent submits that there is no foundation for the appellant’s complaint that there was no evidence to support the apportionment determined by the Arbitrator. The respondent maintains that the Arbitrator specifically referred to the medical evidence which implicated both injuries as being causative, and also took into account the history of the worker’s incapacity. The respondent submits that the rationale for the decision was simple and clear That is, the evidence revealed that the worker maintained virtually full capacity for work up until the 2007 injury. The Arbitrator’s conclusion on apportionment was therefore not illogical or irrational as asserted by the appellant.
Further, the respondent asserts that the Arbitrator’s findings as to apportionment of the liability for the incapacity and for the treatment expenses are not irreconcilable. The respondent submits that on the basis of the evidence before him, the Arbitrator recognised that the 2007 injury played a greater role in the subsequent incapacity than it did in the worker’s need for surgery and medical treatment.
The respondent submits that s 22A(1)(b) provides that the period of time on risk is a “default mechanism” for determining apportionment. It was not argued by either party that the provision had automatic application, although the respondent says it argued at arbitration that it would be appropriate if the matter was one relying on the “nature and conditions” of employment. If that were the case, then the respondent’s share would only be 5 years of the 24 years of the worker’s service. The respondent submits that otherwise, the exercise of apportionment is to be undertaken on a just and equitable basis. It says, as with a common law apportionment, apportionment ought to involve a consideration of the relative importance of the acts of the parties that were causative of the injury, or at least the contributions of the relevant injuries. The respondent says that this was what the Arbitrator did.
The respondent submits that it is important that appellate intervention is restrained because “an apportionment decision relates to a question not of principle or positive findings of fact or law but of proportion, of balance and relative emphasis and of weighing different considerations.”[28] The decision involves, the respondent says, an individual choice or discretion, about which minds might differ. The respondent relies on Central Darling Shire Council v Greeney[29] and Rolls Royce Industrial Power (Pacific) Limited v James Hardie & Co Limited[30] as support for these propositions.
[28] Respondent’s submissions, [35].
[29] [2015] NSWCA 51, [64] and [66].
[30] (2001) 55 NSWLR 626, [60]–[63].
The respondent says in conclusion that the appellant is required to establish that, as a matter of law, the Arbitrator was bound to apply the same apportionment to liability for weekly payments as for the need for medical treatment, which is a proposition that is not supported by the authorities. The respondent maintains that the Arbitrator’s apportionment was within a reasonable range of outcomes, which was based on the evidence, with which the appellate tribunal should not interfere.

The appellant’s submissions in reply

As to ground one – alleged error by apportioning the weekly payments differently to the medical treatment

The appellant responds to the respondent’s submission that there is no authority that requires the Arbitrator to attach the same apportionment to the weekly payments as that agreed upon by the parties for the treatment expenses It says that to apply the same apportionment ignores the evidence. The appellant says that the expert evidence clearly shows that there was a significant injury in 1988, followed by flare-ups of the symptoms from time to time.
The appellant submits that the mechanism of injury in 2007 in isolation was a minor event but made more significant because of the already damaged state of the worker’s back which required further surgery. The appellant asserts that the damage to worker’s back sustained in 1988 was significant and occurred when the respondent was on risk.
The appellant disputes that it argued that the apportionment in respect of treatment expenses automatically flowed onto the apportionment for the weekly payments, so that the Arbitrator had no work to do. The appellant says that its argument is that particularly in the light of the serious nature of the 1988 injury, together with the assessments made by the medical experts, there was no proper basis for the Arbitrator to depart from that apportionment arrived at by those experts. The respondent concedes that while there may be cases where the apportionment in respect of one head of entitlement should be different to another, this was not one of those cases. The appellant submits that the evidence in this case clearly did not support a departure from the assessments made by the medical experts. The only evidence against those medical experts was the opinion of Dr Casikar, whose opinion was expressly rejected by the Arbitrator.
The appellant notes that the respondent seeks to distinguish Widdison. The appellant maintains that it might be arguable that Widdison does not constrain the exercise of the discretion. Nonetheless there needed to be a probative and evidence-based reason as to why there should be a departure from the earlier apportionment, and in this case there was none.
The appellant further notes that the respondent “faintly” makes a submission that if the later injury caused the worker to cease work, then the later injury must be said to have caused the incapacity. The appellant says that this is a new submission, which ought not be permitted to be made on the appeal, but in any event, such a conclusion is not justified on the evidence.
The appellant submits that the respondent has not identified why the evidence supports the Arbitrator’s determination of the apportionment for the weekly payments and the apportionment for the treatment expenses, which were entirely inconsistent with each other.

As to ground two – alleged failure to give adequate reasons resulting in procedural unfairness

The appellant refers to the respondent’s submission that at [77]–[87] of his statement of reasons, the Arbitrator gave proper reasons for his decision. The appellant submits that the Arbitrator’s analysis of what is required in respect of weekly payments was wrong and contends that there was no issue that the worker was entitled to weekly payments and that s 9A of the 1987 Act (substantial contributing factor) was satisfied.
The appellant asserts that in an apportionment, the entire period of the worker’s employment has to be considered. The Arbitrator’s observation that there was no evidence that the 1988 injury had caused anything other than temporary aggravations, the appellant says, was wrong because the 1988 injury led to the surgery and led to the slipping incident in 2007, which led to further surgery.
The appellant contends that the Arbitrator was wrong to confine the medical evidence as he did. The appellant maintains that all the medical experts except for Dr Casikar explained the involvement the 1988 injury had on the injury in 2007 and its consequences. The appellant further submits that to find otherwise than in accordance with the medical expert’s opinions would require a finding that the 1988 injury played no part in the state of the lumbar spine, which could not be the case.
The appellant refers to the Arbitrator’s consideration of the evidence of A/Prof Owler and contends that the Arbitrator treated A/Prof Owler’s evidence in isolation from the remaining experts, and the Arbitrator did not adequately deal with that evidence. The appellant relies on the report of A/Prof Owler dated 21 March 2011, in which A/Prof Owler took a history of the 1988 injury and the worker’s ongoing back condition with progression in the recent years.[31] The appellant contends that the history of continuing and worsening symptoms is inconsistent with the Arbitrator’s findings. Further, A/Prof Owler’s reasons for apportioning 75% of the liability to the 1988 injury included the significance of the long-term consequences of the 1988 injury, the prolonged period of hospitalisation and extended recovery period following that injury and the need to undergo a laminectomy and discectomy. The appellant submits that the Arbitrator simply apportioned on the basis of some periods of partial incapacity where there were “flare ups” and did not take into account the ongoing and worsening symptoms. The appellant submits that the Arbitrator simply ignored the 1988 injury and its significance, which is contrary to the expert medical evidence and is wrong.
[31] Application, p 155.
The appellant asserts that while the Arbitrator referred to the evidence of Dr Davies, Dr Bentivoglio and A/Prof Owler, he did not engage with that evidence. The appellant says that it is not sufficient to simply acknowledge that evidence. The evidence was not limited to the sphere of liability for the treatment expenses but was probative evidence of the issue the Arbitrator was required to determine. Further, there is nothing in that evidence that suggests that the 1988 injury was minor and played no part in the attrition of the worker’s spine or that the “flare ups” were irrelevant or inconsequential.
The appellant maintains that the medical opinions were relevant and probative for the purpose of determining the apportionment.

As to ground three – whether the Arbitrator’s decision was supported by the evidence or was otherwise illogical or irrational

The appellant submits that the errors in the Arbitrator’s reasoning process and use of his discretion are sufficient to make the Presidential member duty bound to intervene, relying on Minister for Immigration and Citizenship v SZMDS.[32] The appellant also relies on BHP Billiton Ltd v Bourke,[33] and asserts that case to be authority for the proposition that it is unnecessary that error be found as a pre-condition to intervention by a Presidential member.
[32] [2010] HCA 16; 240 CLR 611; 84 ALJR 369; 266 ALR 367 (SZMDS).
[33] [2009] NSWWCCPD 117 (Bourke).
The appellant submits that the correct “test” was for the Arbitrator to determine the connection between the incapacity and the injuries, and if that connection was sufficient to determine, in a common sense way, that the incapacity arose partly from one injury and partly from another. The appellant maintains that the Arbitrator was required to look to the extent to which the two injuries contributed to the ultimate outcome, citing HIH Workers Compensation (NSW) Pty Ltd v GIO General Limited.[34]
[34] (2000) 21 NSWCCR 108.
The appellant maintains that the evidence demonstrates that the 1988 injury was a serious injury which led to surgery and caused continuing symptoms and damage to the spine until the 2017 injury. The appellant says that on a just and equitable basis the only logical conclusion open to the Arbitrator was that, had it not been for the consequences of the 1988 injury, the 2007 injury would not have led to the intensive treatment and the worker’s medical retirement. The appellant says that the Arbitrator’s errors are of the kind identified by the High Court in House v The King[35] and are sufficient to merit intervention.
[35] [1936] HCA 40; 55 CLR 499.
In conclusion, the appellant submits that the Arbitrator’s determination was illogical or irrational, was beyond power and constituted jurisdictional error.

Relief sought

The appellant asks for the COD to be set aside, and seeks the following orders:
(a)    the appeal be allowed;
(b)    the amended COD dated 3 June 2019 be revoked and in lieu thereof an order made apportioning the liability of the 2007 injury on the basis of:
(i)25% to the appellant, and
(ii)75% to the respondent;
(c)    in the alternative, remit the matter to another arbitrator for determination, and
(d)    order the respondent to pay the appellant’s costs.
The respondent says that the appeal should be dismissed with costs.

DISCUSSION

Contrary to the submissions made by the appellant in reply to the opposition, in order to succeed in this appeal the appellant must show that the Arbitrator’s decision is affected by error of fact, law or discretion before the Presidential member can intervene.[36] The appellant’s reliance on Bourke as authority for the assertion that it is not necessary that error be found before a Presidential member can intervene is misplaced. The decision in Bourke pre-dated the substantial amendments to s 352 of the 1998 Act, which came into force on 1 February 2011 and is no longer relevant authority on the power to intervene in an appeal.
[36] Section 352(5) of the 1998 Act.
A review of the submissions made both to the Arbitrator and on the appeal discloses that the appellant and the respondent implicitly accepted that each bore some responsibility for a proportion of the liability for weekly payments. The respondent’s submission that in circumstances where a later injury imposed further disability on earlier injuries and led to the incapacity, the later injury could be said to cause the incapacity, is also not on point, given the acceptance by the parties that each bore some liability. The authority relied on by the respondent in respect of that point is George. That authority was decided prior to the legislative amendments to ss 22 and 22A made by the WorkCover Legislation Amendment Act 1995, which made provision for apportionment in circumstances where the incapacity arose partly from one injury and partly from the other. Given the positions taken by the parties, the temporal connection between the later injury and the onset of significant incapacity could enable, but would be limited to, an argument that the 2007 injury made a greater contribution.
The issues for determination by the Arbitrator were therefore of a relatively narrow scope. The relevant considerations were limited to:
(a)    an evaluation of the evidence going to the degree of apportionment;
(b)    an appraisal of the law relating to apportionment (ss 22 and 22A);
(c)    whether the apportionment should be on the basis of the relative periods of risk of each insurer, or if not,
(d)    whether special circumstances required the apportionment on some other basis (s 22A(1)(b)).

The appellant’s first ground of appeal asserts that the Arbitrator fell into error by determining that he was not bound to apportion the weekly payment in the same manner as the liability for the surgery by A/Prof Owler and the lump sum entitlements were apportioned.
The basis upon which the Arbitrator formed the view that a different approach to the apportionment of weekly payments should be taken was that, in his view, liability for weekly payments is defined “not by causation but by the effect a given injury has on an injured worker’s capacity to earn.”[37] The Arbitrator based that conclusion on a consideration of the heading for Division 2 of Part 3 of the 1987 Act, and the heading and contents of s 33 of the 1987 Act. Section 33 of the 1987 Act provides that weekly payments of compensation are payable to an injured worker where the injury results in partial or total incapacity. Division 2 of Part 3 of the 1987 Act deals with when weekly payments are payable and the method of calculating that entitlement. There was no issue in this case that the worker was entitled to weekly payments of compensation or the extent of those entitlements. Those provisions have no relevance as to where the liability for the payments rest. Sections 9, 15, 16, 17, 22 and 22A, which appear in Part 2 of the 1987 Act, deal with the liability to pay compensation. This part of the Arbitrator’s reasons for applying a different apportionment to the weekly payments is flawed.
[37] Reasons, [77].
While the Arbitrator’s reason that the legislature requires a different approach did not support a departure from applying the same apportionment, it does not follow that because the need for surgery and the lump sum entitlements were apportioned in a particular way, the Arbitrator was bound to adopt the same apportionment. This is particularly so given that the apportionment for those entitlements was agreed between the parties. The parties did not agree on the apportionment of the liability for the weekly payments.
The appellant relies on Widdison as authority for the proposition that the Arbitrator was bound to adopt the same apportionment. As the respondent submits, in that case Acting Deputy President Handley did not consider he was bound to adopt the same apportionment but decided:
“Dr Meachin apportioned Mr Widdison’s permanent impairment post 14 May 2003 as 3/4 due to the injury sustained on 18 January 2001 and 1/4 due to the injury sustained on 14 May 2003. In my view, given the Arbitrator’s findings as to Mr Widdison’s physical incapacity both before and after the second injury, it is both just and equitable and appropriate to apportion liability for weekly compensation between the two employers on the same basis for the period from 29 January 2004, pursuant to sections 22(1) and 22A(1)(a) of the 1987 Act.”[38]
[38] Widdison, [34].
The appellant points to no other authority or legislative provision that would lend itself to support the proposition put by it. Whether an incapacity results from an injury is a question of fact to be decided on the evidence using common sense principles. Each case turns on its facts and depending on those facts, there may well be a proper basis for apportioning weekly payments on a different basis to that of treatment expenses or lump sums. In this case, the Arbitrator’s reasoning process in determining the apportionment discloses considerations that would not necessarily be taken into account when determining other apportionments, such as the history that the worker had continued to work on a full time basis, with the exception of occasional “flare ups” until the 2007 injury. Despite the flaw in the Arbitrator basing his conclusion on a consideration of the heading for Division 2 of Part 3 of the 1987 Act, and the heading and contents of s 33 of the 1987 Act, that error has not infected the result, so does not constitute error of the type that would entitle Presidential intervention.[39] It remains therefore that the Arbitrator was entitled to arrive at his own conclusion as to the appropriate apportionment, albeit that one of his reasons was not a proper basis for doing so.
[39] Walshe v Prest [2005] NSWCA 333 at [27].
This first ground of appeal is not made out and fails.
The appellant’s second ground of appeal complains that it was denied procedural fairness because the Arbitrator failed to give adequate reasons for his determination as to the apportionment. The appellant submits that the Arbitrator ought to have provided reasons for:
(a)    rejecting the opinions of Dr Davies, Dr Bentivoglio and A/Prof Owler (which were unchallenged);
(b)    ignoring the evidence of the severity of the 1988 injury, which caused a significant proportion of the instability of the spine following the laminectomy and discectomy, and
(c)    having accepted the opinions of A/Prof Owler and Dr Davies, making a finding that contradicted that evidence.
When a dispute is determined by the Commission, s 294 of the 1998 Act requires a COD to be issued with a brief statement of reasons for the determination. Rule 15.6 of the Workers Compensation Commission Rules 2011 provides:
“15.6 Certificates of determination
(1) A statement of the Commission’s reasons referred to in section 294(2) of the 1998 Act is to include—
(a)the Commission’s findings on material questions of fact, referring to the evidence or other material on which those findings were based, and
(b)the Commission’s understanding of the applicable law, and
(c)the reasoning processes that led the Commission to the conclusions it made.
(2) Without limiting subrule (1), the reasons set out in a statement referred to in subrule (1) are to be stated sufficiently (in the opinion of the Commission) to make the parties aware of the Commission’s view of the case made by each of them.”
Both parties have referred to the various principles arising from authorities relevant to the duty to give reasons. A useful summary of those principles, as they apply in the context of s 294 and r 15.6, can be found in the Presidential decision in Precision Valve Australia Pty Ltd v Nanda,[40] in which Deputy President Roche said the following (citations omitted):
“While the Court of Appeal is conscious of not picking over extempore decisions by judges to look for error, and is mindful of the pressures under which judges work, the giving of adequate reasons lies at the heart of the judicial process (per McColl JA (Ipp JA and Bryson AJA agreeing) in Pollard v RRR Corporation Pty Ltd. These comments are applicable to s 352 appeals from Arbitrators.
The extent and scope of a trial judge’s duty to give reasons depends upon the circumstances of the individual case (Mifsud v Campbell) … Though a judge is not obliged to spell out every detail of the process of reasoning to a finding, it is essential that he or she expose the reasons for resolving a point critical to the contest between the parties (Pollard).
Similarly, though a judge does not have to refer to every piece of evidence, he or she must refer to evidence that is important or critical to the proper determination of the matter (Pollard at [62] citing Beale v Government Insurance Office (NSW)).
Where there is evidence supporting a party’s position, and where a party has presented detailed arguments on that evidence, that evidence and those submissions must be considered in the Arbitrator’s reasons. It is not appropriate for a judge to set out the evidence adduced by one side, and then the evidence adduced by another, and then assert that, having heard and seen the witnesses, he or she prefers the evidence of one and not the other (Ipp JA in Goodrich Aerospace Pty Ltd v Arsic).
Finally, where it is apparent from a decision that a judge made no analysis of the evidence competing with evidence apparently accepted, and gave no explanation for rejecting it, it is apparent that the process of fact-finding has miscarried (Pollard at [66]). This is because, so far as the reasons reveal, the judge made no examination of why the evidence which was accepted was preferred to that of other witnesses (Pollard at [66] citing Waterways Authority v Fitzgibbon).
Having regard to the nature of the proceedings before Arbitrators and the terms of s 294 of the 1998 Act and Pt 15 r 15.6 of the Workers Compensation Commission Rules 2011, which expressly require the Commission to give reasons in support of its decisions, I believe that the above principles apply equally to the Commission’s Arbitrators as to judges.”[41]
[40] [2012] NSWWCCPD 48 (Nanda).
[41] Nanda, [94]–[99].
The Arbitrator provided a detailed summary of the documentary evidence before him. That included:
(a)    the history of the worker’s employment, the mechanism and consequences of the injuries in 1988 and 2007;
(b)    the histories taken by the worker’s treating medical practitioners, and
(c)    the evidence describing the exacerbations of the worker’s back condition that occurred after the 1988 injury and prior to the 2007 injury.
The Arbitrator reviewed at length the details contained in the MAC issued by Dr Davies, including the radiological evidence, and Dr Davies’ assessment of the opinions of Drs Pillemer, Bentivoglio and Casikar. The Arbitrator noted the opinions of Dr Davies, Dr Pillemer and A/Prof Owler about the apportionment of the liability and the reasons provided by each medical expert. The Arbitrator summarised the submissions by both parties made at arbitration.
As both parties indicated, the Arbitrator’s expressed reasoning process for the apportionment appears at [77]–[87] of his reasons. The Arbitrator made the following observations about the evidence:
(a)    Dr Casikar’s opinion was unsupported by the evidence;
(b)    A/Prof Owler considered that the intensive surgical treatment following the 1998 injury may have contributed to the acceleration and degeneration of the L5/S1 disc, and that view was reinforced by Dr Davies;
(c)    the episodic “flare ups” were evidence of the acceleration and degeneration, and
(d)    there was no evidence that the worker’s symptoms following the 1988 injury impacted the worker’s capacity to work to any significant degree.
The Arbitrator considered that the 1988 injury was responsible for the occasional aggravations of the worker’s lumbar spine from 1988 and up to the 2007 injury, so that the 1988 injury was responsible for at least some apportionment of liability.
Turning to s 22A(1)(b), the Arbitrator acknowledged that that section provided for apportionment to be relative to the length of the period of insurance, but that it was open to him to order the apportionment on another basis if the special circumstances in the case made it just and equitable to do so. The appellant raises no issue in respect of that approach taken by the Arbitrator. The Arbitrator considered that it would not be appropriate to apportion the liability on the basis of the relative periods of risk. He considered that there were special circumstances in the case and given the “generality” of the evidence about the occasional aggravations after the 1988 injury, he was satisfied that the back symptoms up until the 2007 injury were “minor irritants” during the worker’s career, which did not significantly impact his capacity for work. For those reasons he apportioned the major liability to the appellant.
The Arbitrator did not reject the opinions of the various medical experts, apart from Dr Casikar’s conclusion, which is not the subject of this appeal. It is clear that the Arbitrator considered the medical evidence, but it is implicit in his reasoning that he took into account that the opinions that were provided were for the purposes of determining the apportionment in respect of other heads of damage rather than for the purpose of addressing the task he had before him.
In assessing whether the reasons are adequate, the reasons must be read as a whole, and the reasons need not be lengthy or elaborate.[42] A fair reading of the Arbitrator’s reasons indicates that he did take into account the opinions of the medical experts, but acknowledged that a consideration of apportionment in respect of weekly payments required him to take into account other factors. The Arbitrator balanced the evidence of the medical experts against the factual background relevant to incapacity.
[42] Beale, 443.
As explained by Kaye AJA (with Tate and Whalan JJA agreeing) in Woolworths Ltd v Warfe:[43]
“The adequacy of the reasons must depend upon the issues, and nature of the proceeding, in any individual case. In an appropriate case, reasons can be adequate by a combination of what is expressly stated and the inferences that necessarily arise from what is expressly stated.”
[43] [2013] VSCA 22, [131].
In the context of the nature of the limited issues the Arbitrator was required to determine, I am of the view that his reasons were adequate to explain the reason why he arrived at his ultimate conclusion.
It follows that ground two of the appeal fails.
The third ground of appeal alleges that the Arbitrator’s determination was not supported by any evidence or was illogical or irrational.
The appellant submits that there was no finding of fact or any available inference to justify a finding that the appellant’s proportion was 75% of the total liability for weekly payments. As the respondent submits, the Arbitrator specifically referred to the medical evidence that both injuries were causative and also took into account the history of the worker’s incapacity. The history of the worker’s incapacity was evidence upon which the Arbitrator could rely, so the appellant’s allegation that there was no evidence cannot be sustained.
Nor can it be sustained that the Arbitrator’s decision has been infected by an illogical or irrational process. The worker’s history of being able to substantially maintain his employment up until the 2007 injury is probative of the question of where the responsibility should fall in terms of the worker’s capacity for employment. The Arbitrator’s conclusion was based upon that uncontested factual evidence. While a different decision-maker may have given greater weight to other evidence, such as the apportionment of liability for the other heads of damages opined by the medical experts, and have come to a different conclusion, that does not demonstrate error of the kind required in respect of this Arbitrator’s factual decision.
As was observed by Crennan and Bell JJ in SZMDS:
“If probative evidence can give rise to different processes of reasoning and if logical or rational or reasonable minds might differ in respect of the conclusions to be drawn from that evidence, a decision cannot be said by a reviewing court to be illogical or irrational or unreasonable, simply because one conclusion has been preferred to another possible conclusion.”[44]
[44] SZMDS, [131].
Applying those principles, it follows that ground three of the appeal also fails.

CONCLUSION

None of the appellant’s grounds of appeal have succeeded. The appellant has failed to establish error on the part of the Arbitrator and there is no basis upon which the Arbitrator’s decision should be disturbed.
Both parties sought an order that the other pay its costs. Section 341(2) of the 1998 Act was introduced to the 1998 Act by the Workers Compensation Legislation Amendment Act 2012 (the 2012 amendments). It provides that the Commission does not have the power to make an order for payment of costs or to determine by whom, to whom or to what extent costs are to be paid. This matter proceeded on the basis that the worker, being a firefighter, was exempt from the 2012 amendments by operation of cl 25 of Pt 19H of Sch 6 to the 1987 Act. Clause 25 provides that the 2012 amendments do not apply to or in respect of an injury received by a police officer, paramedic or firefighter. These proceedings are therefore “in respect of” an exempt injury to the worker who was a firefighter. Generally, costs follow the event. I see no reason to depart from that position and it follows that the appellant should pay the respondent’s costs of this appeal.

DECISION

The amended Certificate of Determination dated 3 June 2019 is confirmed.
The appellant is to pay the respondent’s costs of this appeal.

Elizabeth Wood

DEPUTY PRESIDENT

3 December 2019