Expert evidence in medical negligence claims: holstering the 'gun for hire' trope

Morocz v Marshman [2015] NSWSC 149 

This was a decision dealing with the admissibility of multiple expert reports served in the Plaintiff’s case.

Brief facts

Maria Morocz (Plaintiff), suffered from palmar hyperhidrosis, an excessive sweating of the palms. A condition she had for many years and found embarrassing. In August 2006, she consulted Dr David Marshman, a cardiothoracic surgeon and consented to surgery. 

In 2007, the Plaintiff underwent a bilateral ‘endoscopic thoracic sympathectomy’ (ETS) – a surgical procedure to disrupt sympathetic nerves in the chest responsible for maintaining bodily functions like breathing, blood pressure and sweating.

In the post-operative period, the Plaintiff alleged that she experienced: 

• compensatory hyperhidrosis (sweating in other areas),
• intercostal neuralgia (chest wall pain), bradycardia and other symptoms;
• consequential psychological injury including anxiety and depression.

The Plaintiff commenced proceedings where she alleged the Defendant negligently failed to warn her about material risks associated with the ETS procedure. 

The proceedings were listed for a 10-day hearing from 16 March 2015. Prior to the hearing, the Plaintiff sought leave for several of her experts to give evidence by audio visual link (AVL). The defendant opposed that approach. 

The approach to expert evidence 

The Court took a broad view, ultimately excluding evidence from seven of the Plaintiff’s experts for failing to meet admissibility standards, including:

• Inappropriate expertise: several experts had never performed the ETS procedure nor were they surgeons or medical practitioners. The Court found that their opinions inadmissible being outside their area of expertise. Of one expert, the Court remarked ‘… It is certainly not apparent to me how his study, experience, training or specialised knowledge as a physician specialising in endocrinology and as an ethicist permits or qualifies him to offer expert opinions about the standards of care owed by a surgeon providing specific advice or warnings about the risks associated with a bilateral endoscopic thoracic sympathectomy to a prospective surgical candidate’.
• Lack of reasoning: a report was excluded because the expert offered conclusions with ‘no identifiable reasoning to support his conclusions’. The expert was not a surgeon, and he had not examined the Plaintiff. The Court found that the expert offered ‘only secondhand comments upon the findings and observations of others. It seems to me that it is an essential precondition to the offering of a comprehensible and reliable opinion about the plaintiff’s current medical conditions that any expert medical practitioner doing so should have examined her at least once’.
• Misframing of questions: an expert was asked to address matters such as ‘what are the ethical considerations of the introduction of ETS to the uneducated public when such procedure was described in the promotional literature positively and with enthusiasm?’. 

The Court’s decision resulted in seven of the Plaintiff’s expert reports being knocked out less than two weeks before the commencement of the hearing. That must have been a devastating blow to strategy and no doubt resulted in last minute scrambling to reframe the case. 

The Court ruled in favour of the defendant, and the decision was upheld on appeal.^[6]

Busa v South Eastern Sydney Local Health District Trading as Sydney Eye Hospital [2025] NSWSC 130

Brief facts

Giovanni Busa (Plaintiff) had history of Type two diabetes which led to complications in both eyes. In November 2014, he underwent surgery to repair a retinal detachment with application of silicone oil. On 27 March 2015, the silicone oil was removed during a routine vitrectomy. Shortly after, the Plaintiff returned to the Hospital complaining of soreness in his left eye. An ophthalmic registrar performed a ‘tap and inject’ procedure, where fluid is drawn from the eye to test for infection and antibiotics are injected directly into the eye. 

The Plaintiff alleged that the ‘tap and inject’ was negligently carried out including because the registrar made seven attempts to take a sample. The Plaintiff claimed that he suffered loss of vision in his left eye, ongoing pain and psychiatric harm. 

The approach to expert evidence 

The proceedings were heard before the Court in February 2025. The plaintiff relied on five reports from Dr Pietro Morelli, an Italian ophthalmologist. Issues with Dr Morelli’s evidence included: 

• he had never practised in Australia^[7]
• he provided five reports, but only acknowledged the Expert Witness Code of Conduct in the fourth;
• his reports failed to annex letters of instructions sent to him by or on behalf of the Plaintiff, nor did he set out the assumptions, material facts, or documents he had relied upon;
• extremely problematically, at some point Dr Morelli had also become the plaintiff’s treating doctor and remained so during the hearing. The Court found ‘[t]hat meant that he lacked the same objectivity of the two medicolegal experts relied upon by the defendant. His first duty is to his patient whereas the expert witness’s paramount duty is to assist the Court.’

The Court found Dr Morelli’s evidence non-compliant and unreliable – ultimately affording it little weight. The Court ruled in favour of the Defendant.^[8]

Toon v Central Adelaide Local Health Network [2025] SADC 98

Brief facts

On 19 April 2017, Judah Toon (Plaintiff), awoke with severe swelling, pain, and loss of control in his left forearm and hand. He presented to the Queen Elizabeth Hospital and was diagnosed with compartment syndrome and a closed brachial plexus injury and underwent emergency fasciotomy surgery the same day.

Due to persistent swelling, a second surgery followed on 20 April 2017. He later had debridement on 9 May 2017 and skin grafting on 12 May 2017, remaining in hospital until 29 May 2017, when he self-discharged.

In 2019, further surgery was performed to remove scar tissue and perform neurolysis of the median nerve. 

The Plaintiff alleged: 

• delay in performing the initial fasciotomy;
• negligent surgical technique, including limited incisions and use of a tourniquet;
• failure to provide adequate care, resulting in permanent damage, pain, psychological injury and loss of employment.

The claim was brought under sections 40 and 41 of the Civil Liability Act 1936 (SA). The key issues were:

• whether the standard of care to the Plaintiff was breached; and
• whether any breach caused the Plaintiff’s injuries.

The approach to expert evidence 

The Court found that the Plaintiff’s experts were partisan, with one described as combative and argumentative during cross-examination. Specifically, her Honour Deuter remarked ‘[the Doctor] was not an impressive witness. He was suspicious while being cross examined, and often combative. He at times attempted to guess what counsel was seeking in cross examination, rather than simply answering the question. His evidence was inconsistent in several areas. His attempts to cover up his changed opinions was not the behaviour expected of an expert witness. I find that I cannot rely upon [the doctor’s] evidence, where it is not supported by other evidence’. 

The Plaintiff’s other expert was equally problematic with the Court remarking ‘at this point in the cross examination, [the Professor] became quite combative, slinging questions back to counsel, and not really listening to what was being asked.’

By comparison, the Defendant’s experts were described by the Court as ‘balanced’, ‘considered’, ‘non-partisan’, and ‘impressive’.

The Defendant’s experts provided clear explanations of complex medical issues which supported the surgical approach taken.

The Court ruled for the Defendant, accepting the expert evidence that any delay did not affect the Plaintiff’s outcome as his injury had already occurred prior to his hospital presentation.

Brief facts^[9]

On 8 February 2014, Sue Filmalter presented to her general practitioner, Dr Margaret Swenson, with symptoms suggestive of a urinary tract infection. Based on the pathology results to hand at the time and clinical symptoms, Dr Swenson prescribed Norfloxacin, a fluoroquinolone antibiotic. 

Mrs Filmalter had previously reported an allergic reaction to an unknown antibiotic in South Africa in 2007 and had since refused antibiotics. She alleged that: 

• Dr Swenson failed to properly investigate her allergy history;
• Norfloxacin caused an allergic reaction, leading to extreme photosensitivity;
• this reaction contributed to cerebral vasculitis and a stroke in 2017.

The approach to expert evidence 

Each party relied on expert evidence from a general practitioner. The Court found the Defendant’s expert more persuasive, noting: 

• his evidence was logical, reasoned, and based on correct assumptions; and
• he made multiple concessions and appeared independent and unbiased.

In contrast, the Plaintiff’s evidence was criticised for: 

• hindsight bias and circular reasoning; and
• being poorly reasoned and based on incorrect assumptions. 

The judgment records that at one point in the hearing, the Plaintiff’s expert ‘…burst out laughing and could not contain his laughter, such that court was adjourned to enable [the expert] to compose himself. The laughing was most inappropriate. It was, in my view, a very personal attack upon Dr Swenson which was most unwarranted. That is not the hallmark of an independent witness’. The Court noted that the ‘inappropriate incident’ had no bearing in determining the preference of one expert over the other.

The Plaintiff’s claims under negligence, contract, and the ACL all failed.