The logical relations between the concepts of legal fact and fact, objective fact, legislative fact and adjudicative fact are the legal fact research basic clues.

The author has come to a different conclusion based on historic fact that it is a quasi legislative assembly body in Russia, which builds up the framework of legislative Duma afterwards.

Undercover investigation has been existence and application in China is an indisputable fact, but the law remained silent, did not make a legislative framework for an undercover investigation system.