自刑诉法颁布以来,我国公安机关的侦查活动多数是合法的,能够按照法定程序进行.但近年来,由于一些未经严格挑选和培训的人员,甚至个别有劣迹的人也通过各种关系挤进公安队伍,因此有些干警在侦查过程中存在不同程度的违法行为,严重侵犯了公民的人身权利和民主权利.造成上述现象的原因固然比较复杂,但对侦查活动缺乏有力的法律监督,是其中一个重要因素. Since the enactment of the Criminal Procedure Law, most of the investigation activities of the public security organs in our country are legal and can be conducted in accordance with legal procedures. However, in recent years, some people who have not been rigorously selected and trained have even passed through various kinds of relationships Therefore, some police officers have violated the personal rights and democratic rights of citizens seriously in the course of the investigation, which violate the citizens’ personal rights and democratic rights. Although the reasons for the above-mentioned phenomena are rather complicated, the lack of effective legal supervision over the investigation activities is that One of the important factors.