1. General meritorious service can reduce the benchmark punishment by less than 20%;
2. Those who have made significant meritorious service may have their benchmark punishment reduced by 20%-50%; If the circumstances of the crime are minor, the benchmark punishment may be reduced by more than 50% or exempted from punishment according to law.
Legal basis: People's Republic of China (PRC) Criminal Law.
Article 67 A person who voluntarily surrenders himself after committing a crime and truthfully confesses his crime is a voluntary surrender. Criminals who surrender themselves may be given a lighter or mitigated punishment. Among them, if the crime is minor, the punishment may be exempted.
If a criminal suspect, defendant or criminal serving a sentence who has taken compulsory measures truthfully confesses other crimes that have not been mastered by the judicial organs, he shall be deemed to have surrendered himself.
Although the criminal suspect does not have the circumstances of surrender as stipulated in the preceding two paragraphs, he can be given a lighter punishment if he truthfully confesses his crime; By truthfully confessing one's crimes, particularly serious consequences are avoided and the punishment can be mitigated.
Article 68 Criminals who have made meritorious deeds such as exposing other people's criminal acts and verifying them, or providing important clues to solve other cases may be given a lighter or mitigated punishment; Those who have made significant meritorious service may be mitigated or exempted from punishment.