Feedback provided to eyewitnesses can influence memory as to how confident their previous line-up selections were. Witnesses given confirming feedback remember being more confident than witnesses who are told their selection was incorrect regardless of their accuracy. This can have a powerful impact on judges and juries. In this article, we examine the effect of feedback from a ‘snitch’ (a jailhouse informant). This manipulation often occurs in real cases, despite that fact that snitches could have something to gain from providing information to police. Our participants witnessed a staged crime and then identified the perpetrator from a target-absent line-up. Two days later, participants were provided with feedback and were probed for confidence. Results show that confirming feedback from a snitch has the same effect as a confession made by the actual suspect, and disconfirming feedback reduces confidence. Implications and relation to the extant literature on eyewitness confidence are discussed.