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This term has essentially the same meaning as Accomplice: a person who assists in the perpetration or commission of an offence but is not the direct cause of the Actus Reus. At common law it was possible to be an 'accessory after the fact', that is, to render assistance to offenders after the offence was committed. This meta of 'accessory' is not an 'accomplice' in the modern defintion, and is covered by different legislation.