The criminal law requires citizens not only to avoid violations of norms in the case of realistic compliance, but also to ensure that they have the necessary capabilities to comply with norms. The actor's improper reduction of his or her ability of compliance with norms is the basis and premise for the establishment of a negligent crime. And the criterion used to determine whether an actor has improperly reduced his ability is whether he has violated the duty of care. From the perspective of the nature of the norm, the duty of care is different from code of conduct, the latter is the norm of legal interest protection, whereas the former is the norm of ability maintenance. The function of the duty of care is to keep the actor's ability to comply with the code of conduct above a certain level. An analysis from the points of view of the purpose of criminal law, theoretical thinking and policy effects shows that the monobasic individual standard of the perpetrator should be adopted in the judgment of duty of care. The double-layered duty of care judgment method, which is quite popular in criminal law theory, is not desirable. The laws, regulations, rules and other norms used to fill the blank facts of crime can not only typologically infer the duty of care, but also define the boundary of the allowed risk. However, the specific actor's ability to foresee and avoid is still the "ballast stone" in determining the violation of duty of care in professional negligence crime. On the one hand, only the filling specification related to the maintenance of the capabilities for prediction and avoidance is eligible to be a source of duty of care. On the other hand, the allowed risk can be established only when "the behavior is consistent with the filling specification related to the maintenance of his/her capacity" and "the perpetrator's capacity is actually absent". |