Daniel Bolton and Civil Aviation Safety Authority
[2013] AATA 941
[2013] AATA 941
Division GENERAL ADMINISTRATIVE DIVISION File Number(s)
2013/3717
Re
Daniel Bolton
APPLICANT
And
Civil Aviation Safety Authority
RESPONDENT
DECISION
Tribunal Deputy President PE Hack SC
Date 23 December 2013 Place Brisbane The decision under review is set aside and a decision substituted not to cancel the applicant's class 1 and class 2 medical certificates.
.......................[sgd]…........................
Deputy President PE Hack SC
CATCHWORDS
CIVIL AVIATION – cancellation of medical certificates – skull fracture – extradural haemorrhage – risk of posttraumatic seizures – whether applicant meets medical standard – whether applicant has safety-relevant condition – whether applicant suffering from safety-relevant effects of head injury – whether likely to endanger safety of air navigation – decision set aside and substituted
LEGISLATION
Civil Aviation Safety Regulations 1998, regs 67.150, 67.155, 67.180(2)(e)
CASES
Mulholland and Civil Aviation Safety Authority [2007] AATA 1952
REASONS FOR DECISION
Deputy President PE Hack SC
23 December 2013
Introduction
The applicant, Mr Daniel Bolton, is a commercial pilot by occupation. In March 2013 he was assaulted. His skull was fractured but he has made a good recovery from that injury. The respondent, the Civil Aviation Safety Authority (CASA), was concerned that the skull fracture, together with an associated haemorrhage, put Mr Bolton at risk of experiencing posttraumatic seizures, also referred to as posttraumatic epilepsy, and neurocognitive deficits such that there was an unacceptable risk to the safety of air navigation if he continued to fly.
On 5 July 2013 CASA decided to cancel[1] Mr Bolton’s class 1 and class 2 medical certificates issued to him pursuant to Pt 67 of the Civil Aviation Safety Regulations 1998 (Cth) (the CASR). Without those certificates Mr Bolton may not lawfully perform the duties authorised by his licence, whether as a commercial pilot or otherwise.
[1]The document described in the index to the s 37 documents as the reviewable decision records a decision “to refuse to issue… a Class 1 & 2 Medical Certificate…” (exhibit 1, page 9) however the document sent to Mr Bolton (exhibit 1, page 3) describes the decision as one to cancel those certificates. Despite that, it is common ground that the decision was one to cancel.
Mr Bolton seeks a review of the decision of 5 July 2013.
I have come to the conclusion that cancellation of Mr Bolton's medical certificates is not warranted and that he should be permitted to fly, and to fly commercially. I explain my reasons below.
Background
The factual background is not in dispute. Mr Bolton is 23 years of age. He is fit and healthy. He is the holder of a Commercial Pilot (Aeroplane) Licence and, prior to the incident in March 2013, had been employed for more than two years as a pilot flying single-engine aeroplanes out of Airlie Beach in Queensland. In the early hours of 10 March 2013 he was with friends when he was punched in the right side of his head. He says that he did not lose consciousness and that he can recall the entire event. That may not be correct as his Designated Aviation Medical Examiner (DAME) reported to CASA on 21 March 2013 that he was unable to recall approximately 30 seconds at the time of the incident[2]. Immediately after the incident Mr Bolton noticed what appeared to be an indentation in his skull and he had a headache. He was taken by ambulance to the Proserpine Hospital where a skull fracture was diagnosed. He was transferred to the Townsville Hospital and admitted later that day.
[2]Exhibit 1, page 42.
Mr Bolton is adamant that it was the punch that caused the fracture and that his head did not hit the ground[3]. Dr Ernest Somerville, a consultant neurologist engaged by CASA, points to a reference in the triage note from the Proserpine Hospital which suggests that Mr Bolton was unsure, on his arrival at that hospital after the injury, whether he had been punched in the right side of the head or whether he had been punched and then fallen onto his right side[4]. Ultimately, it seems to me not to matter how the fracture was caused; what matters is the severity of it. I note that that triage note was not, so far as I am aware, in the evidence in the proceedings. It may have been part of the medical records obtained on summons but that material was not tendered in the proceedings.
[3]Exhibit 5, paragraph 8.
[4]Exhibit 9, page 1.
A CT scan undertaken at the Townsville Hospital reported as follows[5],
Findings: There is a depressed, comminuted fracture of the right temporal and parietal bones. The depressed segment has a combined AP diameter of 5 cm and a caudal diameter of 4 cm. There are 3-4 major fragments depressed by up to 1 cm.
A thin underlying extradural haemorrhage is demonstrated at the posterior margin of the fracture measuring approximately 0.5 cm in depth. No subdural or subarachnoid blood is demonstrated. There is no apparent cerebral oedema or definite cerebral contusions.
Conclusion: Depressed right temporoparietal skull fracture with at least 4 major fragments and central depression of up to 1 cm. Minimal associated extradural haemorrhage.
On 13 March 2013 the depressed fracture was elevated surgically. The procedure was performed without complication and Mr Bolton was discharged on 15 March 2013.
[5] Exhibit 1, page 41.
Since the surgery Mr Bolton has remained well, he has not experienced any headaches and has had no episodes of vertigo or any symptoms to suggest any type of epileptic event[6]. He has noticed no problems with concentration, mood, personality or memory function since the surgery. He has successfully undertaken three of the examinations required for his Air Transport Pilot Licence.
[6]Exhibit 2, page 2.
The statutory setting
The starting point must be s 9A of the Civil Aviation Act 1988 (Cth) (the Act). It requires CASA, in exercising its powers and performing its functions, to regard the safety of air navigation as the most important consideration. The Tribunal, in the place of CASA, is similarly obliged.
It is not sufficient for a pilot to have only a pilot licence. Both the Act, by s 20AB(1), and the Civil Aviation Regulations 1988 (Cth) (the CAR), by reg 5.04(1), require the licence holder to hold a current medical certificate appropriate to that licence. In the case of a commercial pilot licence, a class 1 certificate is appropriate and, in the case of a private pilot licence, either a class 1 or a class 2 certificate is appropriate[7].
[7]See reg 5.04(3) of the CAR
By virtue of reg 67.180(1) of the CASR, CASA must issue a medical certificate to an applicant who meets the requirements of reg 67.180(2). Only paragraph (e) of that subregulation is relevant. It provides,
(2)For subregulation (1), the requirements are:
…
(e)either:
(i)the applicant meets the relevant medical standard; or
(ii)if the applicant does not meet that medical standard –
the extent to which he or she does not meet the standard is not likely to endanger the safety of air navigation;
…
In order to meet medical standard 1, and thus qualify for the issue of a class 1 medical certificate, an applicant must satisfy the criteria in table 67.150 of the CASR[8]. Only two items of that table are relevant, item 1.1, which is under the heading “Abnormalities, disabilities and functional capacity”, and item 1.8 which is under the heading “Nervous system”. They read,
[8]See reg 67.150 of the CASR.
1.1 Has no safety-relevant condition of any of the following kinds that produces any degree of functional incapacity or a risk of incapacitation:
(a)an abnormality;
(b)a disability or disease (active or latent);
(c) an injury;
(d)a sequela of an accident or a surgical operation
…
1.8Is not suffering from safety-relevant effects of a head injury or neurosurgical procedure
The criteria to be satisfied to meet medical standard 2 (and qualify for the issue of a class 2 medical certificate) are set out in relevantly identical terms in reg 67.155 of the CASR and the table to that regulation[9].
[9] See items 2.1 and 2.8 of table 67.155 of the CASR.
Content is given to the term “safety-relevant” by reg 67.015 of the CASR. It provides,
For the purposes of this Part, a medically significant condition is safety-relevant if it reduces, or is likely to reduce, the ability of someone who has it to exercise a privilege conferred or to be conferred, or perform a duty imposed or to be imposed, by a licence that he or she holds or has applied for.
The power exercised by CASA in the present case was the power to cancel a medical certificate, conferred by reg 67.255 of the CASR in these terms:
(1)If, after undergoing an examination for the purposes of regulation 67.180 or under regulation 67.230, the holder of a medical certificate fails to meet the relevant medical standard for the certificate (or, in the case of a person who did not, at the time the certificate was issued, meet the standard in all respects, fails to meet the standard in an additional respect), CASA must:
(a) by written notice given to the holder, cancel the certificate; and
(b)if CASA is satisfied that the holding of a medical certificate by the holder will not adversely affect the safety of air navigation – issue to the holder a medical certificate that is subject to any conditions that are necessary in the interests of the safety of air navigation.
By virtue of reg 11.056 of the CASR, CASA may grant an authorisation (a term which includes a medical certificate[10]) subject to any condition that CASA is satisfied is necessary “in the interests of the safety of air navigation”.
[10]See reg 11.015 of the CASR.
The parties’ contentions
The case for CASA starts with the proposition that Mr Bolton suffered a depressed skull fracture with a small extradural haemorrhage. That injury carries with it an ongoing and future risk of posttraumatic seizures. CASA points to studies that demonstrate that skull fractures, depressed skull fractures and extradural bleeding create an increased risk of posttraumatic seizures, particularly in the 18-24 months following the injury. On that basis, Mr Bolton has a safety-relevant condition, a sequela of an accident, that produces a risk of incapacitation and thus he cannot satisfy either item 1.1 of table 67.150 or item 2.1 of table 67.155. Additionally, or alternatively, it is submitted that Mr Bolton is suffering from the safety-relevant effects of a head injury and thus unable to satisfy either item 1.8 of table 67.150 or item 2.8 of table 67.155.
Moreover, CASA says, the condition suffered by Mr Bolton is such that I could not be satisfied that the condition is not likely to endanger the safety of air navigation. It says the imposition of conditions cannot sufficiently ameliorate the danger to air safety posed by Mr Bolton's failure to meet the relevant medical standards. It submits that its decision ought be affirmed and says that Mr Bolton ought not be entitled to apply for a medical certificate until September 2014 when 18 months will have elapsed from the date of the injury.
CASA no longer relies upon the assertion of neurocognitive deficits that was relied upon in the original decision. There is no evidence of such deficits; the evidence of Dr Cameron and Dr Hastings (at least) is to the contrary.
For his part, Mr Bolton contends that he has recovered from his injury and now meets medical standard 1 and medical standard 2. The decision, he says, ought be set aside and a decision made that the medical certificates not be cancelled.
The medical evidence
For some time now the Tribunal, in common with most of the courts and tribunals of this country, has had published Guidelines for Persons Giving Expert and Opinion Evidence (the Guidelines). The Guidelines have the aim of ensuring that those who give expert or opinion evidence do so as independent experts, seeking to assist the Tribunal, rather than as advocates for the cause of the party calling that expert. If followed, the Guidelines ought ensure that the factual assumptions that underlie the opinions expressed are demonstrated, not left to speculation. None of the reports relied upon by the parties to these proceedings came close to satisfying the Guidelines.
Mr Bolton relied upon the report of Dr John Cameron, a consultant neurologist. In addition to his specialist medical qualifications Dr Cameron has a postgraduate Diploma in Aviation Medicine and is a DAME. As it happens, CASA was intending to obtain a report from Dr Cameron for the purposes of these proceedings. His report did not, as it ought, annex the letter of instruction from Mr Bolton's solicitors, it did not list the documentary material considered by him and it did not contain the declaration of duty required by paragraph 14 of the Guidelines, that is, the acknowledgement by the witness of the overriding duty to provide impartial assistance to the Tribunal.
Dr Cameron examined Mr Bolton on 23 October 2013 and arranged for an EEG. Dr Cameron's opinions were expressed in this way[11]:
[11]Exhibit 2, pages 2-3.
Mr. Bolton has made a complete recovery from this depressed skull fracture.
He has no symptoms to suggest any neurological consequence of this head injury, particularly epilepsy at this time.
His MRI imaging of his brain shows no underlying gliosis[[12]] or hemosiderin deposit[[13]] to suggest potential risk for developing post-traumatic epilepsy.
He has normal neurocognitive functioning on my assessment on 23 October 2013.
Depressed skull fractures in some articles have been shown to be associated with a slightly increased incidence of post-traumatic epilepsy while in other studies, depressed skull fractures alone are not associated with increased risk of post-traumatic epilepsy.
This man did develop a small, extradural haemorrhage associated with this skull fracture. The operative notes in particular noted that there was no dural tear and no evidence of underlying contusion on CT imaging at the time.
This man’s small haemorrhage was contained in the extradural compartment and there was no evidence that he suffered any underlying brain injury in this event.
I note also that this man suffered no impaired consciousness at the time of the assault. He had total recollection of events throughout the incident and after. His [Glasgow Coma Score] was 15. He had no focal neurological findings.
Overall, I would assess that this man's risk of suffering post-traumatic epilepsy in this particular case is no more than that of the general population. I believe he is medically fit to return to flying but this obviously will have to be determined by CASA.
I arranged for him to have an EEG, the study was normal and the results are enclosed.
[12]Scarring.
[13]The release of iron from the blood.
Dr John D Hastings was called by CASA. He is a neurologist and aerospace medicine consultant based in Tulsa, Oklahoma. He did not examine Mr Bolton, he merely reviewed his “medical records and other documents provided” by CASA. It was not made clear what those records and other documents were nor was the letter of instruction provided. He did not provide the declaration of duty required by the Guidelines. Dr Hastings said this[14]:
[14]Exhibit 6, page 3.
Mr Bolton's head injury places him at increased risk for [posttraumatic epilepsy] based upon the following:
· Skull fracture
· Depressed skull fracture
· Epidural hematoma
Favourable aspects of Mr. Bolton's head injury are:
· No dural penetration of depressed skull fracture fragments (pneumocephalus was a postoperative finding and air was extradural)
· Non-surgical epidural hematoma (surgery was performed for elevation of skull fragments – not hematoma evacuation). The epidural hematoma was small and clinically inconsequential
· No subdural, parenchymal, subarachnoid or intraventricular bleeding
· No non-hemorrhagic indications of [traumatic brain injury] (e.g. mass effect, midline shift, edema)
· At most mild [traumatic brain injury] by clinical criteria
Based upon the review of medical records and consideration of the scientific literature, it is my professional medical opinion that Mr. Bolton will have achieved a low level of risk for [posttraumatic epilepsy] within 18 – 24 months following his injury. It is my medical opinion that favorable characteristics of his injury place him at the lower end of the risk spectrum than individuals with less favourable characteristics and a greater number of risk factors.
CASA called Dr Pooshan Navathe, its principal medical officer and the primary decision-maker. Some of Dr Navathe’s evidence detailed, quite unnecessarily, the legal framework for regulatory aviation medicine, the processes of aviation medicine decision-making within CASA, risk management and suchlike. The relevance of that evidence was never explained to me. Dr Navathe’s statement discussed, and annexed, various articles from medical research before expressing the opinion that[15],
… given Mr Bolton's history of head injury, there is a significant risk of [posttraumatic seizure]. There is a substantial or real and not remote possibility that Mr Bolton will suffer a [posttraumatic seizure] whilst in flight. Were Mr Bolton to suffer a fit whilst at the controls of an aircraft in flight, then this would pose a clear threat to the safety of air navigation, and thus I have reached the conclusion that the extent to which Mr Bolton fails to meet the class 1 and class 2 medical standard is such that I cannot issue him with a medical certificate under r.67.180 of the CASR.
[15]Exhibit 8, paragraph 87.
Dr Navathe’s witness statement concluded in this way:
90.Having reviewed all three specialist reports, I remain convinced that I have made the safest decision in refusing Mr Bolton a Class 1 and 2 medical certificate at this time. I have formed the view that is supported by all three specialists, that Mr Bolton does not have a severe head injury, and ceteris paribus [all other things being equal] will be able to obtain medical certification after a period of 18 – 24 months has elapsed from the time of the injury.
91.I acknowledge that I have an overriding duty to provide impartial assistance to the Tribunal. No matters of significance have been withheld from the Tribunal
Despite the fact that the statement does contain the declaration of duty required by the Guidelines it could not be plainer that Dr Navathe is an advocate for his own decision. I do not propose to have any regard to his opinions. For the future I would trust that CASA’s Legal Branch would exercise independent judgement in deciding what witnesses ought be relied upon and the content of their statements. They ought, obviously enough, be confined to matters that are relevant and witnesses ought be those who can truly provide an independent opinion.
Finally, CASA relied upon evidence (including a report of 4 November 2013) of Dr Ernest Somerville, a consultant neurologist. I have already made mention of the reference in Dr Somerville's report to a document from the Proserpine Hospital which is not in evidence in the proceedings. The failure to comply with the Guidelines is exemplified by this passage from Dr Somerville's report[16]:
The following opinion is provided in response to your letter of 30 October 2013 and telephone conversation with Dr Pooshan Navathe on 1 November 2013. Information about Mr Walker's [sic] medical condition is limited to the documents provided with your letter of 30 October 2013.
It is not known what documentary material was provided to Dr Somerville nor is it known what was conveyed to him by Dr Navathe in the conversation on 1 November 2013. Moreover, it is highly irregular that one expert witness, who is as well the primary decision-maker, was apparently briefing another expert witness in terms not disclosed. The danger of such a practice ought to have been evident. The vice is merely compounded by the failure to make clear what information was conveyed.
[16]Exhibit 9, page 1.
In any event, Dr Somerville concluded as follows[17]:
Mr Bolton is at increased risk of seizures as a result of the head injury. The two characteristics of the injury that increase his risk are the depressed skull fracture and the extradural haematoma. However, there was brief, if any, loss of consciousness, very little, if any, post-traumatic amnesia and no cortical injury clinically or on imaging. Epidemiological studies group patients with common characteristics and their ability to subdivide these groups is generally limited by numbers of subjects. The studies above would include Mr Bolton in the categories of skull fracture, depressed skull fracture and extradural haematoma. However, this group would include patients with much more severe head injuries. Multivariate analysis attempts to exclude those other factors, so that the risk factor being examined does indeed account for most of the increased risk on its own. In Mr Bolton's case, the most pessimistic estimate would give him a 2.5% risk of a seizure occurring in the first 12 months and 0.8% risk in the 2nd 12 months.
The impact of this increased risk on Mr Bolton’s safety to fly depends not only on its size but the likelihood that if a seizure occurs, it will happen while operating an aircraft and consideration of the consequences of a seizure while flying.
[17]Exhibit 9, pages 2-3.
Consideration
The first question that arises is whether Mr Bolton fails to meet the medical standard. Am I satisfied that he has no safety-relevant condition of the type described in item 1.1 of table 67.150 of the CASR and the equivalent item in table 67.155 and that he is not suffering from safety-relevant effects of a head injury? The evidence of Dr Cameron satisfies me that he does not have any such condition and that he is not suffering from safety-relevant effects of a head injury.
There is, in my view, no evidence that Mr Bolton has any safety-relevant condition. The term "condition" is not defined. Given that "safety-relevant" is defined in reg 67.015 of the CASR by reference to "a medically significant condition" it must be used in the sense of a state of health. The evidence of Dr Hastings and Dr Somerville (and that of Dr Navathe) does not suggest that Mr Bolton has any condition, medically significant or otherwise, rather it is to the effect that, as a consequence of his injury, he has a higher than normal risk that he has such a condition. The case of Mulholland and Civil Aviation Safety Authority[18], referred to in CASA's Statement of Facts, Issues and Contentions, was an entirely different case. Mr Mulholland had experienced occasions of loss of consciousness brought about by a temporally insufficient flow of blood to the brain. What was controversial in the case was the cause of the condition; the condition itself was not in issue.
[18] [2007] AATA 1952
The same is true of "safety-relevant effects of a head injury". Mr Bolton sustained a head injury but there is no evidence that he is suffering from any effects of that injury.
There is no doubt that if Mr Bolton had posttraumatic seizures his ability to perform the duties imposed by a pilot's licence would be reduced (or would be likely to be reduced), that is, it would be a safety-relevant condition. But where the evidence falls short of pointing to the existence of either a "condition" or an "effect of a head injury", and points merely to an increased risk of the presence of a condition or the possibility of an effect, questions of likelihood of reduced ability do not arise. The better view of the evidence, I consider, is that Mr Bolton currently meets the medical standards.
But even if that evidence was to be regarded as being evidence of a condition or of an effect of a head injury I have a distinct preference for the evidence of Dr Cameron. He alone had the benefit of a clinical examination of Mr Bolton. He concluded that Mr Bolton’s risk of posttraumatic seizures was no greater than that of the general population. The studies relied upon by the other witnesses, he said, considered the full range of head injuries not merely the very mild head injury suffered by Mr Bolton. It was Dr Cameron's opinion that a skull fracture increased the risk of posttraumatic epilepsy only if there had been penetration of the dura or if there had been bleeding in the cavities of the brain. Neither occurred in the present case. That evidence satisfies me that, had I concluded that Mr Bolton did not meet the medical standards, his present medical condition is not likely to endanger the safety of air navigation.
I will then set aside the decision to cancel and substitute a decision that Mr Bolton’s medical certificates not be cancelled.
I certify that the preceding 32 (thirty -two) paragraphs are a true copy of the reasons for the decision herein of Deputy President P E Hack SC ..........................[sgd]..............................................
Associate
Dated 23 December 2013
Date(s) of hearing 11 November 2013 Counsel for the Applicant Mr P Lithgow Solicitors for the Applicant Maitland Lawyers Solicitors for the Respondent Legal Branch, Civil Aviation Safety Authority
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