| The exposure and rehabilitation of a series of unjust cases such as She Xianglin, Zhao Zuohai, Nian Bin and Hugejiletu shows the achievement in the gradual progress of China Criminal Justice and the determination to reform our judiciary. The reports on these cases also make the idea of governing the country by law more popular. However, redressing the unjust cases is just the first step in criminal judicial reform. We should think more about how to avoid unjust cases in today’s tide of nomocracy, so that we can enhance the credibility of the judiciary. The trumped-up case is frequently. What causes this problem is the deficiency of legal supervision. The legal supervisory institution fails its duty. Most medias who report the aforementioned cases focus on the illegal behaviors during the criminal investigation such as extorting confessions, they believe that illegal investigation activities cause the unjust cases and undermine judicial credibility. Thus, the procuratorial supervision in investigation should be an important component of the lawful supervision of criminal procedure. This article make procuratorial supervision in investigation legally defined at first. Then the article briefly discusses foreign legislation. And last but not least, based on the legislative situation of criminal proceedings in our country, the paper analyses the contents, characteristics and malpractice in China’s procuratorial supervision in investigation. In the end, the thesis try to find the improves by comparing domestic and foreign legislation and combining with The Opinions on Some Issues of Improving the Judicial Accountability System. |