Hazrat Sha'bi (may Allah have mercy on him) and Ibrahim (may Allah have mercy on him) say that it is permissible to testify after hearing.

23149 - (And from) (1) Ubaidah (from Ibrahim) (2) (they both said) (3): The testimony of hearing is permissible.

Hazrat Hasan (may Allah be pleased with him) says that if a person hears something from a group and then comes to the judge, he will say: "They did not make me a witness, but I heard such and such."

It is narrated from Hazrat Furat that fifty dirhams were owed to me by a person. I went to him and demanded the debt, and another person was listening to all of this. I took him to Hazrat Shurayh (may Allah have mercy on him). That person denied my claim. Hazrat Shurayh (may Allah have mercy on him) said: Where are your witnesses? I said: One person was listening to all of this when he admitted to owing me the dirhams. He said: Call that person. I called him and he gave testimony. Hazrat Shurayh (may Allah have mercy on him) said to that person: Stand up and pay him his due.

Hazrat Shurayh (may Allah have mercy on him) would not accept the testimony of a mentally disturbed person.

Hazrat Sha'bi (may Allah have mercy on him) would not accept the testimony of a mentally disturbed person.

Ibrahim (may Allah have mercy on him) said that the testimony of a mentally disturbed person is not valid.

Hazrat Shurayh (may Allah have mercy on him) did not consider the testimony of a mentally disturbed person to be valid. Hazrat Amr bin Harith says that the same should be done with the testimony of an oppressor or a traitor.

Hazrat Sha'bi (may Allah have mercy on him) says that when the polytheists come to you and appoint you as their judge according to the decision of the Muslims, then do not take them towards a decision other than Islam, or else withdraw yourself from between them and their co-religionists and turn away from them.