Sandra Battersby v Allan; Darrel Battersby v Allan  NSWSC 1724 was an interlocutory decision in the course of claim arising from a neurosurgical procedure following which the claimant suffered hemiplegia. The defendant applied for orders in relation to the claimant’s expert, who was a neurologist not a neurosurgeon.
The court held at  – :
The unchallenged evidence before me is that a Neurologist is required to have a detailed understanding of (inter alia) the anatomy of the brain, and the deficits resulting from damage to the brain. The evidence also establishes that a Fellow in Neuropathology (Dr Milder having held such a Fellowship since 1981) is required to have expertise in the macroscopic and microscopic examination of the brain. The opinion expressed by Dr Milder in the present case is clearly based upon his knowledge of, and his training, study and experience in, those matters. It is also evident that Dr Milder’s opinions are based, at least in part, upon matters of physiology, an area in which he has considerable training, study and experience.
I am mindful of the observations of the Court in Farquharson (at ) regarding the importance of considering the precise character of the question upon which the expert evidence is sought to be given. In the present case, the precise character of the question is centred upon a surgical procedure to an area of the anatomy in which he has considerable training, study and experience. It may be the case that ultimately, the weight to be attached to Dr his opinion is less than that to be attributed to the opinion of a Neurosurgeon. However, questions of admissibility must not be confused with questions of weight: Farquharson at .
The court also addressed the late service of an expert’s report, which was allowed at  –  on the basis of exceptional circumstances:
That said, it remains the case that the hearing of the proceedings will not be delayed as a consequence of the service of Dr Webster’s report. Moreover, and although the report was served outside of orders made by the Court, counsel for the defendant candidly, and properly, conceded that there would be no demonstrable prejudice to the defendant if the report were admitted. Perhaps even more importantly, if the report were excluded it would leave the plaintiffs in a position where they would be precluded from relying upon important expert evidence in support of their respective cases. That, in addition to the matters to which I have already referred, is sufficient in my view, to constitute exceptional circumstances.
In the course of submissions it was suggested by counsel for the defendant, albeit feintly, that it was relevant to take into account that in the event that the report of Dr Webster were excluded, the plaintiffs may have some cause of action against their solicitor. If that be a possibility, it is one which is of little weight in the discretionary exercise: Repco Corp Limited v Scardamaglia  1 VR 7 at 15 per Smith J; Simms v Western Sydney Area Health Service  NSWSC 445 at - per Burchett AJ.
It follows that in my view, exceptional circumstances are established for the purposes of r. 31.28(4)(a) and leave should be granted to admit the report of Dr Webster.