The leniency system for guilty plea and punishment is known as the“consultative judicial model”. However, in the judicial practice of guilty plea and punishment cases, there are still defense lawyers who defend their innocence from the aspects of fact determination, lawapplication and evidence rulesapplication.The accuracy of fact determination, the principle of legality for a crime and the principle of presumption of innocence constitute the legitimate basis of such innocence defense. The inclusiveness of the system of confession and punishment, the limited independent status and professional ethics of the defender, the need to prevent the unjust, false and wrong cases, and the need to form a multiple defense force also provide a reasonable space for it.Lawyers should pay attention to the validity of defense opinions and ensure the synergy of defense strategies when defending innocence in such cases. Public security organs, procuratorial organs, peolpe’s courts and other state organs should respect and guarantee the innocence of lawyers in cases of confession and punishment.