论法律行为生效的“适法规范”——公法对法律行为效力的影响及其限度

违反强行法的法律行为无效是各国的共同规则，可称为法律行为生效的“适法规范”。强行法应仅指公法上的强行法，私法上的强行法是自治规范，违反它的效力最严重的不过是“不生效”而不是“无效”。违反公法的法律行为是否无效，必须探究公法的目的，并运用比例原则来限制对公法目的的解释，以进一步区分公法责任与私法责任。民法也不能排除地方性法规和行政规章的适用。违法和违反公序良俗的功能截然不同，两者不能统一。

Norms of legality in relation to the validity of juristic acts （rechtsgeschiift）： the influence of public law on the effect of juristic acts and its limitations

It is a common principle in all countries that juristic acts that violate jus cogens are invalid. This may be termed ＂norms of legality＂ in relation to the effect of juristic acts （Rechtsgeschaft）. This refers only to jus cogens in public law, since jus cogens in private law is self-governing or autonomous in nature and its violation results at worst in ineffectiveness rather than invalidity. In determining whether legal acts that contravene public law are valid, the objectives of the related public laws must be examined and the principle of proportionality applied to limit the interpretation of the objectives of the public law in question, in order to further distinguish obligations in public law from those in private law. Local laws and administrative rules cannot be excluded completely in the application of civil law. Violation of the law and violation of public order and good custom have totally different effects and cannot be treated as the same thing.