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This article describes circumstances in which a witness's previous statements can be admitted in evidence to rebut his testimony in court. Such a situation usually arises during Cross-examination, but it is not entirely unheard of during Examination-in-chief.

Previous inconsistent statements in cross-examination

Under s.4 of the Criminal Procedure Act (1865), the prosecution may adduce evidence of a previous inconsistent statement to rebut the witness's evidence-in-chief, if the witness does not admit to making the previous statement. The usual procedure in modern practice is to ask the witness if he wishes to stand by his testimony before adducing the previous statement. In practice, most witnesses will change their testimony if faced with a conflicting earlier statement. If the witness indicates that he will stand by his testimony, the cross-examining party may adduce rebuttal evidence, even to the extent of calling witnesses in rebuttal.

At common law, the previous statement was admissible only to the extent that it allowed the jury to assess the credibility of the witness. However, under the Criminal Justice Act (2003), s.119 provides that a previous statement is admissibile as evidence of the facts stated.

Previous inconsistent statements in evidence-in-chief

This situation should be relatively rare -- a party ought to be satisfied that a witness he intends to call will 'come up to proof'. If the witness does not provide useful or persuasive evidence, it is not usually permissible for party that called the witness to attempt to impeach him. This means that a previous inconsistent statement will be inadmissible. Of course, the calling party is entitled to call other witnesses whose view of events contradicts that of the unfavourable witness.

However, if a witness is not merely unfavourable, but gives testimony that is adverse to the party who called him, leave of the court may be sought to have the witness declared hostile (see hostile witness).