In the "Huacheng Case", the Supreme People's Court amended the rule of invalidity based on the principle of good faith and affirmed the validity of the contract when the application of the rule of invalidity would result in serious improper consequences in an individual case. Taking the legislative purpose as the boundary to make a distinction between purposive restriction and legal amendment, the court used the amendment function of the principle of good faith as the methodological tool in the "Huacheng Case". In this case, one party, by claiming that the contract was invalid on the ground of its own violation of law, abused the legal system of invalidity. In light of the facts of the case, especially the "special situation" in this case, that is, the construction contract had been basically fulfilled and the project had been accepted, and after balancing, the court came to the conclusion that the importance of the realization principle overrode the sum of the substantive and formal reasons for the application of the rule, and the rule should be amended in accordance with the principle of good faith. The process of the amendment function of the principle of good faith can be sorted out as follows:deciding that strict application of rules will produce serious improper consequences; ascertaining the legislative purpose of the rule and demonstrating that the case cannot be properly dealt with within the legislative purpose; introducing a new factor of balance, namely the principle of good faith; balancing; and amending the rule to produce the proviso. |