Legal basis: Article 29 of the Prison Law of People's Republic of China (PRC). If a criminal sentenced to life imprisonment or fixed-term imprisonment does repent or perform meritorious service during his sentence, his sentence may be reduced according to the results of prison assessment. Those who have made one of the following major meritorious deeds shall be given a reduced sentence: (1) preventing others from engaging in major criminal activities; (2) reporting major criminal activities inside and outside the prison, which is verified by investigation; (three) there are inventions or major technological innovations; (4) sacrificing oneself to save others in daily production and life; (five) outstanding performance in resisting natural disasters or eliminating major accidents; (6) Having made other significant contributions to the country and society.