It think about that presumption regulation if can use for the paternity testing in practice the rule of law.

The establishment of presumption rules should be regulated because of the reasons of the criminal substantive law and procedural law, and should follow a series of basic principles.

Based thereon,it proceeds with a discussion on the interrelations between rationality of expression and uncertainty of the rule.

the rule of refusing testimony assumption in Chinese "Some Provisions of the Supreme People s Court on Evidence in Civil Procedures" can not reflect the basic features of assumption and leave too much space to the discretional evaluation of evidence which blocks realization of its advantages such as benefit litigation economy.