In a conversation with his boss, which was overheard by other officers, the policeman lamented that his colleague "doesn't do any work" and is "a liar, I don't speak to liars".
The statement may seem harmless enough, but Italy's highest court on Tuesday ruled it was tantamount to abuse, Il Messaggero reported.
The Court of Cassation said that calling someone in the "delicate role of a policeman" a "liar" is "unacceptable".
Meanwhile, telling someone "I'll kill you", at least within marriage, is acceptable, the same court ruled last week as it threw out a case against a woman for threatening her husband during an argument, Catania Today reported.
The court concluded that threatening to kill your husband can't be taken too seriously.