Confronting a peer's dishonest behavior is more problematic than confronting the same behavior in a direct report. When you're in a position of authority over someone, it's part of your job to monitor their behavior. With a peer, you're in the uncomfortable position of being a bystander, torn between getting involved and being accused of meddling or ignoring the transgression and being guilty of aiding and abetting. The best strategy is to outwardly assume that this is all a matter of misperception rather than actual malfeasance. You are warning your peer that their actions could be mistaken for dishonest actions by someone who didn't know them as well as you do. Transparent or not, this gambit should be effective enough to at least put the other person on notice and, it is hoped, prevent future problems.
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