Informing witnesses of the general nature of a defence case could jeopardise the fairness of the trial, the Law Society has said in response to a consultation on draft prosecution guidance.
The Crown Prosecution Service guidance, Speaking to Witnesses at Court, sets out the role played by prosecutors at or before court to ensure witnesses give their best evidence.
It states that prosecutors should not provide the detail of, discuss, or speculate on the specific questions a witness is likely to face or discuss with them how to answer the questions.
But witnesses can be informed about the general nature of the defence case where it is known, such as mistaken identification, consent, self-defence or lack of intent.
However, the Society believes this could create a ‘significant risk’ that some witnesses will tailor or embellish their evidence.
It said: ‘There is a balance to be struck between providing information to the witness that may improve their experience in giving evidence, on the one hand, and risking the fairness of the trial by alerting the witness in advance to those aspects of their evidence which are challenged, on the other.’
The first response of the witness to the defence case, the Society said, was important ‘in assessing the witness’s veracity’, which could only be ascertained by the jury or magistrates by observing their demeanour in court.
‘If this element of surprise is removed by informing the witness beforehand is lost, it will allow the witness to “dig in their heels” and to attempt not give an objective account of what they saw [or heard].’
Introducing the change, the Society further argued, would shift the adversarial system of criminal justice towards a more inquisitorial system.