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[1894] AC 57 (HL). The defendants were convicted for murdering an infant whom they had offered to care for in return for money. A significant element of the prosecution case was that the dead bodies of other dead infants had been found buried in the grounds of the defendants' house. On appeal, the defendants argued that this evidence ought not to have been admitted, as it was merely EvidenceOfBadCharacter -- it did not increase the likelihood that the defendants were guilty of the present offence.

Lord Herschell LC stated the general position with respect to evidence of past criminal activity:

'It is undoubtedly not competent for the prosecution to adduce evidence tending to shew that the accused has been guilty of criminal acts other than those covered by the indictment, for the purpose of leading to the conclusion that the accused is a person likely from his criminal conduct or character to have committed the offence for which he is being tried

However, he went on to say that evidence did not become inadmissible just because it tended to show that the defendant had been guilty of criminality in the past, so long as it was relevant to an issue before the court. As to evidence that would be relevant, he gave two examples: evidence that

...bears upon the question whether the acts alleged to constitute the crime charged in the indictment were designed or accidental...

and

...to rebut a defence which would otherwise be open to the accused...

In the present case, the evidence of the dead bodies was admissible because the defendant's had claimed that the victim's death had been accidental, and the presence of other dead bodies in the garden did tend to defeat that argument.

See also: Dpp v boardman (1975), Dpp v p (1991).