Related על כתובות 2:3

Witnesses that said, "We testify about Ploni that he is a son of a divorcée" or "son of a halutzah (woman who was eligible for levirate marriage but went through the halitzah ceremony instead)", "a natin (descendant of a Canaanite Temple servant)", or "a bastard (mamzer)", [but] before their testimony was investigated in court, they said "We are liars"—behold they are believed. If after their testimony was investigated in court they said "We are liars", they are not believed. This is the rule of the matter: Witnesses that testify to declare something impure, pure, to distance, to bring closer, to forbid, to permit, to exempt, to obligate—if, before their testimony was examined in court they said "We are liars", they are believed; [but] if after their testimony was investigated in court they said "We are liars", they are not believed.