After a bank robbery in Patna, the prosecution examines several witnesses. Which of them is an…

An accomplice is a guilty associate who took part in the crime with the accused, so the accomplice here is "Rafiq, who took part in the robbery together with the accused". Section 138 of the BSA makes such a person a competent witness, and a conviction on his corroborated testimony is not illegal; section 119 lets the Court presume he is unworthy of credit unless corroborated in material particulars. A decoy, an informer or a bystander does not share the criminal intent, so none of them is an accomplice.