False witness
The evidence of 鈥榚xpert鈥 witnesses who are inexperienced, inexpert, and/or easily led can lead to miscarriages of justice, as well as unwelcome notoriety.
If the duties of an expert are not carried out in the manner expected by the courts, the ramifications can be significant.
Where evidence is wholly or partially rejected, the impact on a trial can be fatal.
A notable and, unfortunately, not infrequent example of the potentially serious ramifications can be seen in a recent British case, where an expert鈥檚 failings caused the collapse of a trial involving a multi-million pound carbon-credit fraud, and the significant risk that prior trials might also be tainted.
Lack of academic qualification
The expert鈥檚 lack of academic qualification was discovered when he could not recall if he had passed any A-Levels and, in addition, admitted that he had never read a book on the subject matter of the case.
He also accepted that he had kept sensitive material obtained from the police in a cupboard under his stairs, some of which was destroyed. It was also shown that he had cut and pasted his witness statement from previous trials.
The trial judge stated that the expert was 鈥渘ot an expert of suitable calibre. He had little or no understanding of the duties of an expert. He had received no training and attended no courses. He has no academic qualifications. His work has never been peer-reviewed.鈥
Reefer madness
Experts are expected to provide evidence in order to assist the court in reaching an informed decision based on knowledge, expertise and experience.
This is a duty addressed in this jurisdiction by of the Rules of the Superior Courts, which makes it clear that the duty to assist the court overrides any duty an expert might feel is owed to a party paying their fee. This is also an obligation that experts are required to acknowledge in their reports.
An expert should be able to stand by their evidence to such an extent that they can truthfully say the same opinion would be given, even if they were acting for the other side.
A 鈥榟ired gun鈥
What they clearly shouldn鈥檛 do is act as a 鈥榟ired gun鈥 with the aim of strengthening the case of the instructing principal.
This issue, however, continues to receive negative attention in court, despite various judges鈥 efforts to highlight experts鈥 obligations.
In what are colloquially known as the Ikarian Reefer principles, the duties of an expert are described as follows:
- Evidence presented to the court should be the independent product of the expert, uninfluenced as to form or content by the exigencies of litigation.
- Evidence should provide independent assistance to the court by way of objective, unbiased opinion with regard to matters within the expert鈥檚 expertise.
- Evidence should state the assumptions or facts upon which the expert鈥檚 opinion is based. In addition, the expert should consider material facts that could detract from the concluded opinion.
- Evidence should make it clear whether a particular issue falls outside of the expert鈥檚 area of expertise.
- If the expert鈥檚 opinion is not properly researched as a result of insufficient data, then this must be stated.
- If, after an exchange of reports, an expert has a change of view on a material matter, such change must be communicated to the other side.
- Where expert evidence refers to photographs, plans, calculations, etc, these must be provided to the opposite party at the same time as the exchange of the reports.
The principles have been reflected in Irish judgments, most recently in the 2019 Supreme Court case of , where expert evidence was challenged but, ultimately, it was held that the evidence was 鈥渘ot sufficient to conclude 鈥 that the testimony of the expert witnesses 鈥 was affected by the exigencies of litigation鈥.
Adopting the test in the case, the court held that it had not been proved that the evidence was 鈥渁nything other than independent, objective and unbiased鈥.
Other cases in Britain also highlight the importance of the above guidelines, where a failure to comply with them can result in the downfall of an expert鈥檚 evidence and possibly the claim.
In , the court held, perhaps unsurprisingly, that the expert testimony could not be given due weight where the experts involved had not read all of the relevant papers before writing their reports.
No independent checks
Similarly, in , an expert鈥檚 evidence was disregarded in full and deemed 鈥渆ntirely worthless鈥 as there were no independent factual checks carried out, and the assertions of the expert鈥檚 principal were repeated without care.
Ultimately, the evidence was deemed to have 鈥渕ade a mockery of the oath鈥, and the expert was viewed as little more than a 鈥渕outhpiece鈥 for the claimants.
In addition, in the recent trials in Britain, the use of one expert by the Serious Fraud Office was referred to as a 鈥渄ebacle鈥, with Lord Justice Gross remarking: 鈥淚t鈥檚 not a matter to be downplayed when the Crown in a major prosecution calls a witness who is wholly out of his depth鈥.
He also queried: 鈥淗ow did it come about that he was instructed when he lacked expertise? We are very concerned as to how he can have been instructed, the due diligence, and how it came to light.鈥
Expertise
Whether or not a witness is an expert will depend on their particular expertise, qualifications and experience in the area. In , it was made clear that the opinions of experts are only admissible in evidence on the subject areas where they are expert.
The burden of establishing expertise rests with the party calling the witness, and must be shown before the witness gives evidence.
It was, however, held in Martin v Quinn (1980) that a witness giving evidence about their qualifications is prima facie evidence of his or her qualification, unless rebutted.
Although an expert is dealt with under the as 鈥渁 person who appears to the court to possess the appropriate qualifications or experience about the matter to which the witness鈥檚 evidence relates鈥, no such civil definition is available.
Criminal definition
As the criminal definition is not overly prescriptive, Irish and British case law provides some guidance as to our understanding of the expertise required of an expert witness.
In ascertaining whether a witness can be considered an expert, a good starting point is the basic set of questions of Russell LCJ in R v Silverlock (1894):
- Is he [expert]?
- Is he skilled?
- Has he adequate knowledge?
Other judicial pronouncements also assist. In Galvin v Murray (2001), Murphy J stated that 鈥渁n expert may be defined as a person whose qualifications or expertise give an added authority to opinions or statements given or made by him within the area of expertise鈥.
In McFadden v Murdock (1867), it was held that expert status can be achieved through experience, such as a shopkeeper becoming an expert in the grocery business.
Further, in the case of (2003), it was noted that evidence should not be allowed in court where the witness providing it was not adequately experienced or qualified to do so.
Immunity
The British Supreme Court found, in 2011, that there was no justification for expert-witness immunity from suit continuing, and it was abolished. As a result, experts can now be sued in contract and in tort for the evidence detailed within their reports and given in court in Britain.
In Ireland, immunity is still recognised. However, the courts continue to encourage experts to comply with their duties by alternative means.
For example, in the recent case of , Barton J stated that the failure of the expert witness to disclose relevant material was 鈥渞eprehensible and is to be deprecated鈥, and the court directed a copy of the judgment be forwarded to the Medical Council of Ireland.
Law reform
Given the wide-reaching consequences that can result from unsound expert evidence, a 2016 report of the Law Reform Commission (LRC) recommended the following four duties of expert witnesses be set out in legislation:
- An expert has an overriding duty to the court to provide independent, impartial and honest evidence,
- An expert has a duty to state the assumptions and facts upon which their evidence is based 鈥 in addition, the expert must fully inform themselves of any fact that could detract from their evidence,
- An expert must confine themselves to matters within their scope of expertise, and
- An expert must act with due care, skill and diligence.
The LRC also recommended abolishing expert immunity and replacing it with civil liability, limited to circumstances in which it was established that the expert had acted with gross negligence in giving evidence or preparing a report falling far short of the standard of care expected of such an expert.