This article, authored by Ann-Marie Christie, MAPS’ in-house solicitor, is based on insights drawn from an EWI article. It provides invaluable insights into the critical issues of independence, bias and conflict of interest for expert witnesses. Highlighting key principles from the Civil Procedure Rules and case law, it explores how experts can maintain objectivity, avoid unconscious bias and ensure their evidence remains credible and effective in court proceedings.
When can experts decide whether they believe or disbelieve the evidence before them and does that stray into bias and cause them to lose their independence?
At this year’s EWI annual Sir Michael Davies Lecture, The Hon. Mr Justice Trower, a British High Court Judge and a member of the Civil Procedure Rule Committee, delivered the keynote speech.
Mr Justice Trower provided some invaluable insight into the issues of independence, conflict of interest and bias and the consequences for an expert at court when these fundamental components are compromised.
What does independence mean for an Expert Witness?
Every expert will need to think about independence, whatever the forum is or their expertise.
The concept of independence is clearly set out in the Civil Procedure Rules (CPR) Part 35 Practice Direction and within the Guidance for the instruction of experts in civil claims.
The Practice Direction states:
2.1 Expert evidence should be the independent product of the expert uninfluenced by the pressures of litigation.
2.2 Experts should assist the court by providing objective, unbiased opinions on matters within their expertise, and should not assume the role of an advocate.
2.3 Experts should consider all material facts, including those which might detract from their opinions.
Any trace of a lack of independence by an expert can result in a submission by the opposing party that the evidence lacks objectivity, or worse, that the evidence should be rejected entirely.
The Oxford Dictionary defines independence as “freedom from external control or support” or “the freedom to act or think without influence from others.” Therefore, any discussions between lawyers and experts should not lead experts to include material drafted or subtly guided by the lawyers.. Reports that appear to be manufactured can severely damage an expert’s credibility and undermine their effectiveness.
Succinctly put by Lord Dyson in the case of Jones v. Kaney [2011] UKSC 13 at paragraph 99: ‘There is no conflict between the duty owed by an expert to his client and his overriding duty to the court. His duty to the client is to perform his function as an expert with the reasonable skill and care of an expert drawn from the relevant discipline. This includes a duty to perform the overriding duty of assisting the court. Thus, the discharge of the duty to the court cannot be a breach of duty to the client. If the expert gives an independent and unbiased opinion which is within the range of reasonable expert opinions, he will have discharged his duty both to the court and his client. If, however, he gives an independent and unbiased opinion which is outside the range of reasonable expert opinions, he will not be in breach of his duty to the court, because he will have provided independent and unbiased assistance to the court. But he will be in breach of the duty owed to his client.’
(See also Writing Medico-Legal Reports in Civil Claims an Essential Guide, 2nd Edition – Giles Eyre and Lynden Alexander.)
Conflicts of interest and potential bias
The Civil Procedure Rules make it very clear that an expert must immediately disclose any conflict of interest as soon as they become aware of it. While a conflict of interest does not always render an expert’s evidence inadmissible, it is important that an expert provides full disclosure.
An expert can expect to be challenged on the independence of their work during cross-examination to test their primary duties to the court. Ultimately, it is for the court to decide what weight will be afforded to their evidence should a conflict of interest be disclosed.
Conscious bias can arise when an expert offers opinions to suit a specific outcome, disregarding whether the opinion reflects their true position.
Unconscious bias is slightly more complicated and flows from what respected Australian judge Justice Peter McClellan has called “the influence of the inevitable human desire to win the debate”. Without realising it, experts who regularly give evidence for the same client may be more prone to unconscious bias than those experts that have more balanced instructions and act for both sides.
Experts must act with integrity and remember that they are there to assist the judicial process and the court, rather than the paying party.