As far as modern law is concerned, the law can generally only be applied to events and behaviors that occurred after the entry into force, but not to events and behaviors before the entry into force, that is, the principle of non-retroactivity of laws is adopted.
Extended data
To solve the problem that the retroactivity of judicial interpretation leads to the cross application of the old and new criminal laws and the new and old judicial interpretations, we must adhere to one principle: effectiveness of the criminal law is superior to judicial interpretation. That is, judicial interpretation should completely follow or submit to the provisions of the criminal law.
Under the condition that judicial interpretation does not conflict with criminal law, it can of course be used as the basis for judicial treatment at the same time; However, when there is a conflict between judicial interpretation and criminal law, the provisions of criminal law should be observed first, and the legislative provisions that should be observed cannot be adjusted or even changed according to the provisions of judicial interpretation.
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People's Network-Retroactivity of Criminal Judicial Interpretation