accessory, in criminal law, a person who, though not present at the commission of a crime, becomes a participator in the crime either before or after the fact of commission. An accessory before the fact is one whose counsel or instigation leads another to commit a crime. An accessory after the fact is one who, having knowledge that a crime has been committed, aids, or attempts to aid, the criminal to escape apprehension. In a misdemeanor and in treason there is no distinction between principals and accessories. In some states the common law distinction between principal and accessory before the fact has been abolished, and the accessory before the fact is prosecuted as a principal. The penalties for being an accessory are usually much less severe than those meted out to the principal. Except where statutes provide differently, an accessory cannot be tried without his consent before the conviction of the principal, unless both are tried together. If an accessory is called as a witness, the court must decide if he is also an accomplice, because the testimony of an accomplice must be corroborated. An accomplice has been defined as any person who could be prosecuted for the crime of which the defendant is accused. This would include principals and accessories before the fact; depending on the jurisdiction and the facts of the case it might also include conspirators (see under conspiracy) and accessories after the fact.