An expert witness provides a medical opinion on the facts of the case.
This is different from the role of the professional witness.
The expert witness' duty is to the court.
Training is available from specialist companies.

What does an expert witness do?

An expert witness assists a court, tribunal or committee by providing an impartial medical opinion.

They will be experienced in a relevant specialty, and their evidence will help the court reach a decision about the case. Lawyers will decide how to proceed with a case largely based on the expert opinion.

The expert witness will not normally have had direct clinical contact with the patient before legal proceedings start.

Who can act as an expert witness?

Practitioners with sufficient experience in their specialty to be able to give a reliable and informed opinion to the court.
At least 10-15 years' experience in a specialty may provide the necessary background knowledge to become an expert witness.
Information and training is available from the Expert Witness Institute.

What are the duties of an expert witness?

You must understand your role and follow the GMC guidance that sets out the duties of a doctor when acting as a witness.

An expert witness must:

be impartial - your duty is to the court, not the person who instructs or pays you
confine statements to areas of relevant knowledge or direct experience
include all relevant information and provide a balanced opinion
declare any conflicts of interest without delay
not disclose confidential information without consent (other than to parties to the proceedings, or where obliged by law or ordered by the court)
inform appropriate people if you change your view on a material matter
make sure that instructions you are given are clear and unambiguous.

Expert witness duties can include:

a clinical examination of the patient
writing a report
literature search
discussions with lawyers and other experts
attending hearings
giving evidence based on your report.

For civil cases, you should be familiar with the Civil Procedure Rules (Rule 35) and your report must comply with them. You may be vulnerable to criticism if it does not.

Further advice

If you're considering accepting instructions as an expert witness, read our detailed guide on what this involves.

Members can also contact our medico-legal advisers by phone or email for specific advice and support.

Acting as an expert witness

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