Experts, documents and the duck test: the lessons from Ruffell v. Lovatt

Under English law, any expert witness should provide his “objective, unbiased opinion on matters within his expertise”. No expert witness should ever assume the role of an advocate.1 The recent decision of HH J Iain Hughes QC in Ruffell v. Lovatt shows how the advocate exposes and exploits any material that could support a finding against the other side’s expert of a lack of objectivity, bias or acting as advocate. The court expects an expert to be careful, thorough, balanced and to exercise judgment

The facts in Ruffell
The Claimant was a passenger in a car driven by the Defendant which collided with a tree. As a result the Claimant injured her neck and right leg. The Defendant admitted liability at an early stage but not the nature, extent and causation of the Claimant’s alleged injuries northe quantum of damages. The main issue was whether the Claimant haddeveloped complex regional pain syndrome (“CRPS”) and suffered continuing pain and disability.
The Claimant’s oral evidence contrasted her busy active life before the accident with her restricted and isolated life afterwards. Each party relied on the evidence of a pain expert and a psychiatrist. These experts provide reports, joint statements and were cross-examined at trial.

The Judge’s assessment of the Claimant’s pain expert’s expert evidence
I refer to the Claimant’s pain expert as Dr A. The Judge’s view was that Dr A’s evidence was “so flawed” he “could not rely on any contentious aspect” of it.
The Judge acknowledged that Dr A was a conscientious, experienced consultant doing his best for his patients in his clinics. It was not material that Dr A whilst giving oral evidence at times started to laugh at propositions put to him by counsel and also had a habit of lapsing into lecture mode. However there were five reasons for rejecting his evidence.

  • Dr Aagreed it was necessary to understand fully the Claimant’s pre-accident history before diagnosing CRPS. However, Dr A hadno real knowledge or understanding of the Claimant’s extensive pre-accident history. Dr A had positively asserted that the Claimant was fit and well before the accident. Her medical history showed that that was not right.
  • Dr A was neither careful nor forensically thorough. When he prepared his first report more than 4 years of the Claimant’s medical records were missing and important events had occurred in that period. Dr A did not ask for the missing records, qualify his conclusion or express a tentative conclusion. There was no evidence he noticed that the records were missing.
  • In his written reports Dr A was dismissive, in off hand or rude terms, of the Defendant’s experts’ views. In the Judge’s view the Defendant’s experts were “equally well-qualified doctors” and one of them had more experience in years working in pain clinics and more peer-reviewed publications referencing CRPS than Dr A.
  • In his oral evidence Dr A was dismissive of those who did not agree with his “rigidly held opinions”. The other three experts accepted that a diagnosis of CPRS was controversial. Dr A dismissed such an approach as “absolute rubbish and nonsense”. This dogmatic approach was inconsistent with the obligation of an expert witness to consider and acknowledge where there is a range of opinions, even if the expert for his own reasons rejects them.Dr A also said that the expert psychiatrists for both sides had “concocted” a diagnosis. Using such objectionable terms displayed a lack of balance and judgment.
  • Dr A’s evidence was combative. He repeatedly acted as the Claimant’s advocate. There was a lack of balance and much argument in his evidence. Rather than answer a question directly Dr A would often sidestep and respond with an argument to support the Claimant’s position. In contrast the other three medical experts listened to the questions and answered them briefly and as best as they could.

What are the lessons for the lawyer from this?

    • check the material you give to your expert, is it complete? Help your expert to consider all material facts.

When reviewing your expert’s draft report, consider:

  • the accuracy and thoroughness of the draft: has your expert considered all the material you have supplied? Are there careless mistakes in the draft?
  • should your expert qualify his opinion in some way: for example if the expert cannot reach a definite opinion as there is insufficient information the expert must make that clear.2
  • whether there is range of expert opinion: if there is a range of opinion on the matters dealt with in the report, your expert should summarise it and givereasons for his own opinion.
  • the tone and balance of your expert’s expressed views: has your expert expressed himself in writing in a balanced and objective manner rather than argumentatively, dogmatically, or with a lack of balance. Your expert needs to be educated in the standards expected by the Courts
  • warn the expert before he gives evidence to remain objective and to answer the questions not to advocate his client’s position.


There should be no misunderstanding. The required approach is clear. To be credible the expert must behave in a professional manner. As the poet said “When I see a bird that walks like a duck and swims like a duck and quacks like a duck, I call that bird a duck”. It is very difficult to persuade a Judge that an expert’s views and opinions are objective and unbiased if they are expressed in an ill considered and imbalanced way.

1. Cresswell J in National Justice Cia Naviera SA v. Prudential Assurance Co Ltd (The Ikarian Reefer) [1993] 2 Lloyd’s Rep 68, 81. He referred to Lord Wilberforce in Whitehouse v. Jordan [1981] 1 WLR 246, 254, Garland J in Polivitte Ltd. v. Commercial Union Assurance Co. plc [1987] 1 Lloyd’s Rep 379, 386 and Cazalet J in Re J [1990] F.C.R. 193. See also CPR 35 paragraph 2.22. CPR PD paragraphs j 2.4 and 3.2 (8), and Guidance paragraph 13

Author:  Marion Smith QC