The “Several Provisions of the Supreme People's Court on Evidence in Civil Litigation” as a whole affirmed and expanded the self-admission rules, but the “Several Provisions of the Supreme People's Court on Evidence in Civil Litigation” Article 8 paragraph 2 continued the legal spirit of Article 92, Paragraph 3 of the “Comprehension and Application of Judicial Interpretation of the Procedural Law” stipulates that the effect of preclusion of the self-admission system is restricted. Why the “Several Provisions of the Supreme People's Court on Evidence in Civil Litigations” restrict the effect of preclusion of self-admission system? The fundamental reason is the traditional inertia of the absoluteness of facts exploration and the pursuit of substantive justice values. The direct cause is the actual demand for regulating collusive litigation. However, to construct a normative self-admission system should adhere to the relativization of facts exploration, coordinate the relationship between party autonomy and facts exploration, and pursue a balance between procedural justice and substantive justice. The practice of restricting the effect of preclusion to regulate collusive litigation does not pay for the gains. The most preferable way to regulate collusive litigation should be to abolish pre-determinant force and set an honesty obligation for the parties. Tracing back to the source, the self-admission system originated from the doctrine of debate and naturally should return to the doctrine of debate. The self-admission system that returns to the doctrine of debate centers on the effect of preclusion. Article 8 paragraph 2 of the “Several Provisions of the Supreme People's Court on Evidence in Civil Litigation” loses legitimacy. The application of the effect of preclusion of self-admission system must consider the difference and relativity of the litigation environment of different cases.