The system of stained witness refers to a criminal individual device under which the testimony by a stain witness may exempt him from criminal prosecution or sanction, or lessen the potential santion, he would ortherwise, be imposde on.

• 污点证人制度是指如果有犯罪污点的人为了国家的利益而作证,就可以免受刑事追诉或被给予刑事上的从轻、轻或者免除处罚待遇的一种刑事司法措施。