Backbiting is a sin very clearly distinguished by the shariah. The Messenger (SAW) asked the Sahabah, do you know what is backbiting. And they responded saying, Allah (SWT) and His Messenger know best. Mufti Yusuf Moosagie spoke on the topic.
Nabi (SAW) then said, speaking about your brother or sister in a manner that he or she dislikes (that is backbiting). The Sahabah then asked, "Oh Nabi of Allah, what if my brother is the way that I am saying, if he possesses these qualities or did the action I'm referring to? Nabi (SAW) mentioned that if you speak about him that is backbiting and if he does not possess those qualities you have slandered him.
However, there are times when backbiting is permissible.
· When one is rectifying injustice. It is permissible to engage in gibaah if you are rectifying injustice. So he will mention “so and so has wronged me”. By saying this he is not committing gibaah, because he wants to get justice.
· When a person seeks help to change a wrong and return the wrongdoer to the right path. This is when you go to someone who has the power to change the wrongdoer, for example, a parent and you speak to them about what their child has done. In this instance, you are not committing gibaah, because your intention is to bring about good change.
· When a person requests a fatwa or verdict, and here you speak to a scholar and explain to them what someone has done in order to get Islamic advice. In this instance, it is better to not mention names when you are speaking.
· When you warn a Muslim about evil and advise them to stay away from other people, you are allowed to speak about such people.
· When you declare certain narrators and witnesses as unreliable, it is permissible to speak about them.
· When you seek advice or counsel about someone before marriage, going into a partnership or business dealing with that person.
· When you see someone who is studying fiqh under someone who is involved in bid'ah (innovation). Or you see someone studying under someone who is a frequent sinner, then you may advise the student but in a good manner. This should be solely in the interest of the unwary student.
· When a person is in a position of authority which he does not administer correctly, either because he is incompetent or he is a faasiqh which is a frequent sinner. Here is will be necessary for you to go to higher authorities to have him removed.
· When a person publicises his own sins, example drinking usury, bribery etc., it is permissible to mention their sin publicly but you are not allowed to speak about anything else.
· When a person needs to identify someone when a certain person is only known by a certain defect. Only if this is the only way to identify them and not to devalue them.
The general rule when it comes to backbiting in terms of the shariah is that it is impermissible it is a way of losing your good deeds and transferring it to others. By engaging in gibaah you are passing your good deeds onto others. However, there are certain instances in which you can mention negative things about people, provided it is for a greater good, as mentioned above.
May Allah (SWT) guide us all.