There are a few synonyms that can be used for the phrase "pass the buck." One possible phrase is "shift the blame," which implies that someone is trying to avoid taking responsibility for a mistake or problem. Another synonym is "evade accountability," which suggests that someone is shirking their duty to admit fault or make amends for a situation. A third possible phrase is "ducking responsibility," which implies that someone is trying to avoid facing the consequences of their actions. These synonyms all describe various aspects of the same behavior, which involves trying to avoid taking responsibility for one's actions or decisions.