The accused couple in the "Laiyuan Case" ended with no prosecution by the procuratorate,which reflects the lack of uniform standards for defining the time conditions of justifiable defense in China. The defense time can be divided into starting time and ending time,the identification of which has been studied by the academic community,but limitations exist inevitably. In identifying the time conditions of justifiable defense, the danger theory should be taken as the theoretical guideline:the starting time needs to be defined in accordance with the urgence of danger, and the ending time on the basis of the elimination of danger. And the definition of danger must be based on the theory of subjectivity which includes defender recognition and general people recognition. Both the defender and general people angles have advantages and disadvantages, and the binary theory of subjectivity combining the defender recognition and general people recognition contributes to more accurate danger identification. Through analysis on the basis of the danger theory and binary theory of subjectivity, we can conclude that the final verdict of the "Laiyuan Case" is correct and reasonable.