Marilyn Stowe Blog

Expertise in the dock

Family lawyers are many things but they are not scientists, accountants, pathologists or paediatricians. So how do they tackle those cases which turn on complicated  financial, medical or scientific issues? They call on ‘expert witnesses’.

This courtroom staple, sometimes also called a professional witness or judicial expert, is defined by Wikipedia as:

“…a witness, who by virtue of education, training, skill, or experience, is believed to have expertise and specialised knowledge in a particular subject beyond that of the average person, sufficient that others may officially and legally rely upon the witness’s specialized (scientific, technical or other) opinion about an evidence or fact issue within the scope of his expertise…”

Of course, for an expert witness to have any value in courtroom proceedings, their expertise must be trustworthy, as their statements can – and often do – have a huge influence on the outcome of particular cases. If they are mistaken, confused, or express themselves badly on the witness sand,  the outcome could be disastrous.

One of the most vivid examples of the way in which experts can cast a shadow over an entire case is that of solicitor Sally Clark, who was infamously convicted of the murder of her first two children in November 1999. Both had died suddenly in early infancy. Shortly after the second death she was arrested and charged with their murder.

During the trial at Chester Crown Court, paediatrician Sir Roy Meadow was summoned as an expert witness and famously told  jurors that the chances of two children from a well-to-do, non-smoking family dying from cot death (also known as ‘sudden infant death syndrome’) were as low as one in 73 million.

This figure had a decisive impact at the original trial and first appeal but was highly controversial. It was publically repudiated in 2001 by the Royal Statistical Society. Criticism of the figure focused on two separate issues. Firstly unidentified environmental factors could make a second cot death in the same family considerably likelier than  a separate incidence in another family. And secondly, the one in 73 million figure failed to account for the relative likelihoods of the two different explanations for the deaths of the children: double cot death (rare) versus double infant murder (even rarer).

Around this time, I began to investigate the case myself on a pro bono basis and eventually uncovered the fact that prosecution pathologist Alan Williams had been aware of a crucial piece of evidence since 1998 but had not disclosed it. This evidence that suggested one ofClark’s children could have died from a bacterial infection.

These two findings contributed toClark’s release at her second appeal in 2003. As a direct result of the case two other women who had been convicted of murdering their children had their convictions overturned.

Tragically for her family, Sally was unable to come to terms with the experience and was diagnosed with a number of serious psychiatric issues after her release. She was found dead at her home from alcohol poisoning barely four years later.

Earlier this year, in his high profile report Judicial Proposals for the Modernisation of Family Justice Mr Justice Ryder had this to say about expert witnesses in family courts: “…they are misused and overused”.

He urged a cautious, moderate approach:

“In every case, the judge should be able to say: is your expert necessary i.e. to what issue does the evidence go, is it relevant to the ultimate decision, is it proportionate, is the expertise out with the skill and expertise of the court and those already involved as witnesses by reference to the published and accepted research upon which they can rely and of which the court has knowledge.”

That is a detailed, legal way of saying: if a particular expert witness cannot contribute anything useful to the proceedings, they should not be in the courtroom. Or their findings should not be relied upon.

In one recently published case, findings presented by two expert witnesses were so blatantly contradictory that a special hearing was held to resolve the issue. A mother involved in care proceedings had undergone hair strand testing to demonstrate that she was no longer taking drugs. In such tests the chemical composition of hair strands is analysed in a laboratory. Initial results from a company called Trimega Laboratories suggested that the mother had taken both cocaine and opiates quite recently. She strongly denied this and was eventually given permission to have a second test carried out by a different laboratory. Results from the second laboratory – Concateno Cardiff Ltd – supported her claim that she had not taken any drugs for the previous four months.

As a result of this deadlock, Mr Justice Baker referred the matter to the Right Honourable Sir Nicholas Wall, President of the Family Division of the High Court. Shortly before this hearing, Trimega admitted that their test results had been tainted by human error.

In a subsequent judgement, Mr Justice Baker stressed the importance of access to expert witness evidence:

“…in appropriate circumstances the family justice system requires, and will continue to require, expert evidence to ensure that it makes the right decisions about the future of children. I repeat what I said in Re JS [2012] EWHC 1370 (Fam) at para 47: ’Whilst the courts always have to be vigilant to guard against the proliferation of experts in family proceedings, the court must, in my judgment, always have available to it the necessary expertise to make the right findings in these important and difficult cases.’ ”

I share Mr Justice Baker’s belief in the importance of appropriate expertise. But I cannot help but wonder what might have happened if the mother in the original hearing had not been granted permission to have her hair strands tested a second time. Caution must be the watchword whenever outside expertise is introduced into any case.

Photo of Chester Crown Court by Dennis Turner