“警察圈套”是美国刑法合法辩护中的一项内容。在我国的司法实践中也存在利用“警察圈套”来侦破案件的情况。从刑罚的目的———预防犯罪与犯罪产生的原因及刑法公正性的角度看 ,“警察圈套”背离了现代司法、侦查活动的公正价值 ,有损于政府的威信。因此 ,“警察圈套”的合法性值得质疑 “Police trap” is a part of the legal defense of criminal law in the United States. In our country’s judicial practice, there are also cases of using “police trap” to detect cases. From the perspective of the purpose of punishment --- the causes of crime prevention and crime and the impartiality of criminal law, “police trap” deviated from the fair value of modern judicial and investigation activities and undermined the prestige of the government. Therefore, the legitimacy of “police trap” is questionable