The Grand Ayatollah Shobairi Zanjani answered a question about discussing with others the fault of the person who accepts bribe.
Question: When everyone is aware of the situation that a person accepts bribes, if we say in a gathering: Yesterday such a person accepted a certain amount of bribe. Is this considered backbiting?
The Grand Ayatollah Shobairi: If they (the people in the gathering) or a person from that gathering who is unaware (of the bribery), it is backbiting. Even in the case of informing, if that person is reviled by the listener, it is not allowed unless it is on the condition that it is for the purpose of forbidding wrong.
Source: PERSIAN SHAFAQNA
source : shafaqna.com