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It frequently happens that a court hearing takes place some time after the events under consideration. By the time of the hearing, the witness may already have written an account of the events, or made notes, or given a formal statement to the police. The question that then arises is what evidential value these notes or statement have. Usually the use of previous statements arises in one of the following contexts.

1. A witness may wish to refer to he his own earlier statement to refresh his memory before or during his testimony (see witness refreshing memory)
2. A witness may wish to draw attention to the similarity between his oral testimony and the earlier statement in order to bolster his credibility (see previous consistent statement)
3. During cross-examination, council may wish to adduce a previous statement as evidence to rebut recent fabrication (see previous inconsistent statement)