The workshop

Expert witnesses

OT  poses a monthly scenario from a practitioner. This month, we look at what the role of being an expert witness involves for optometrists

Man in a library

The scenario

Benjamin, AOP member

"As an experienced optometrist who has been practising full-time for more than 20 years, I am looking to expand my skillset in a non-clinical capacity and have been considering becoming an expert witness. Can you tell me more about what this role involves and the duties it would require of me?"

The advice

Dr Chris Pamplin, UK Register of Expert Witnesses

In July 2016, Optometry Today reported on the criminal trial of optometrist Honey Rose in which expert witnesses who had been drawn from a number of disciplines, including optometry, were heavily involved on behalf of the prosecution and defence teams.

The published report describes the case as the first-ever charge of gross negligence manslaughter against an optometrist, and offers an insight into the role of the expert witness in a criminal trial.1 Regardless of the type of litigation, though, any optometrist considering expert witness work must understand their role in the proceedings and remain impartial, regardless of the instructing party. This article aims to explore what is required from an expert witness.

Experts and expert witnesses

An expert is anyone with knowledge or experience of a particular field or discipline beyond that to be expected of a layman. An expert witness is an expert who makes this knowledge and experience available to a court to help it understand the issues of a case and thereby reach a sound and just decision.

There is, currently, no precondition imposed by English law on the qualities required of an expert witness. It is for the courts, on a case-by-case basis, to make a judgment of the individual’s qualities and to weigh the expert’s evidence in accordance with this judgment.

The College of Optometrists offers some guidance2 on practising as an expert witness, with lots more relevant information contained in the textbook Getting Started as an Expert Witness.3

What is expert evidence?

The fundamental characteristic of expert evidence is that it is opinion evidence. It should be independent, objective and unbiased. It must provide as much detail as is necessary to allow the judge to determine that the expert’s opinions are well founded. It will often include:

  • Factual evidence obtained by the witness requiring expertise in its interpretation
  • Factual evidence which, while it may not require expertise for its comprehension, is linked inextricably to evidence that does
  • Explanations of technical terms
  • Opinions based on facts adduced.

Duties of an expert witness

The overriding duty of an expert witness is to the court. They must be truthful as to fact, thorough in technical reasoning, honest as to opinion, and complete in the coverage of relevant matters. This applies to written reports as much as to evidence given in court. At the same time, the expert assumes a responsibility to the client to exercise due care with regards to the investigations carried out and to provide opinion evidence that is soundly based. 

To fulfil these duties adequately, it is vital that the expert should also have: 

  • Kept up to date with current thinking
  • Familiarity with the provisions of the various court rules.


The fees experts charge are, in large part, market driven. What’s more, fees charged in cases that are paid for from public funds are subject to Ministry of Justice caps.4

The UK Register of Expert Witnesses conducts a biannual survey on expert fees amongst its members.5 The current average hourly rate for report writing for optometrists for non-legal aid civil work is £241 per hour (2015 data).5

Why be an expert witness?

Expert witness work can be a rewarding adjunct, both intellectually and financially, to an existing professional workload. However, anyone considering entering the fray should take care to understand the nature of the role and the expert’s duties and ethical considerations therein.

For free access to expert witness support and guidance, plus membership information, visit the website and subscribe to the UK Register of Expert Witnesses’ free e-wire service. By signing up, users will gain access to over 100 newsletters and will receive monthly updates.


  1. Optometry Today, Clinical trial of optometrist begins 
  2. College of Optometrists, Expert witness 
  3. Edition 2 (2015), published by J S Publications 
  4. made for rates for civil cases, which are identical to those for criminal cases
  5. To take part in the current survey from the UK Register of Expert Witnesses
  6. To view details of survey results since 1995. 

About the author

Dr Chris Pamplin has been editor of the UK Register of Expert Witnesses since it was established in 1988. He provides professional support and education to expert witnesses. He is also a regular contributor to meetings and publications that consider aspects of expert evidence in the UK.