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The general principle is that a witness's previous consistent statements are not admissible, as they add nothing to the probative value of the witness's testimony (R v roberts (1942)). Previous inconsistent statements may be admissible in cross-examination (see previous inconsistent statement). and, in exceptional circumstances,evidence in chief (see HostileWitness).

There are a number of exceptions to this general rule, of which the most frequently encountered are as follows.

1. The recent complaint exception in trials for sexual offences (and, under the Criminal Justice Act (2003), any offences)
2. Rebuttal of an accusation that the witness's testimony is fabricated. In such a case, the exception is only engaged if there is a specific allegation of fabrication -- accusing the witness of untruthfulness in general will not suffice (R v oyesiku (1972)).
3. A Confession is prima facie admissible, unless s.76 of Pace applies, and the fact that it serves only to reinforce a point brought out under cross-examination does not restrict its admissibility
4. An exculpatory statement or MixedStatement is admissible as a concession to fairness (RVStorey1968), although with a mixed statement the judge has a discretion to warn the jury that the inculpatory parts are more likely to be true (R v duncan (1981)). However, the evidence is only admissible to prove the credibility of the witness, not to prove the facts (and this does not seem to be changed by the Criminal Justice Act (2003)).
5. Where the previous statement is a photograph or photofit picture that identifies a person, place, or thing (R v cook (1982)). In Cook it was held that neither the rule against Hearsay nor the rule against narrative would apply to such identification evidence. Under the 2003 Act, such evidence is capable of amounting to hearsay, but is admissible as identification evidence under s.120(5) if tendered by the witness making the identification