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At common law, EvidenceOfBadCharacter that showed a disposition towards committing a particular offence was admissible, in certain circumstances, against the defendant in a criminal trial. The jargon term 'similar fact evidence' became common to describe this meta of evidence, because its admissibility turned on whether the previous conduct had similar facts to the charge at issue.

There is a large volume of case law on similar fact evidence. Once the CriminalJusticeAct2003 comes fully into force (it is not in force at the time of writing), none of these cases will be binding on the courts, as this case law will be abolished. However, the new Act does recognize (s.103(1)(a)) evidence that the defendant has a 'propensity to commit offences of the kind with which he is charged', so it is likely that the earlier case law will contine to provide guidance on whether, for example, particular facts show such a propensity.

See evidence of disposition for more details.