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This section describes the procedures followed when a witness is called to give evidence in a court hearing or trial.

In a criminal case the side calling the witness will usually question that witness in the presence of the court (ExaminationInChief). Then the other side will have an opportunity to ask questions (Cross-examination). Finally, the calling side can question again (Re examination), to clarify any points made in the cross-examination. Usually the prosecution makes it case first, so the preliminary witnesses are generally prosecution witnesses. Then the defence makes its case, often calling its own witnesses. In civil cases, this procedure is often not followed as rigorously and, in any case, examination-in-chief often takes the form of preparation of written statements rather than a presentation in open court.

When a particular party calls a witness, that party will typically be assuming that the witness will adduce evidence helpful to his own case. Particular procedures exist for situations where that proves not to be the case (see hostile witness and UnfavourableWitness).

Witnesses should normally give evidence under oath (see: Sworn evidence) and in open court, but it is recognized that this is not always practicable or desirable. Witnesses may give evidence by TV or video recording in special cases, e.g., where a witness is a child (see: Special measures for witnesses). In general, a person called to give oral evidence should not be allowed to see other documents during the examination. However, this will be allowed for documents made by the witness earlier in the investigation (to refresh the witness's memory, for example). Except in particular cases, English law does not require Corroboration of witness evidence.

Witness must, in general, answer all questions put to them. However, there is a general right to refuse to answer questions if the anwers would lead to Self-incrimination.

Evidence law