Hazrat Amr bin Nafi’ narrates that Hazrat Ali (may Allah be pleased with him) said: There are two types of stoning (rajm): one is that in which the ruler throws stones first, then the people; and the other is that in which the witnesses throw stones first, then the ruler, then the people. The narrator says: I asked Hazrat Hakam,“What is the stoning by the Imam?”He replied: When the woman gives birth to a child or she confesses. And the stoning by the witnesses is when they give testimony.