Despite the considerable attention criminologists devote to the study of policing, they tend to ignore one of its most important functions. Detectives comprise approximately 16% of law enforcement personnel and play a major role in the public’s image of the police through their successes or failures. This scholarly lacuna is even more surprising given the gateway position held by police investigators; unless a crime is solved and an individual arrested, the entire remainder of the criminal justice system—prosecutors, defense attorneys, judges, juries, probation, prisons, parole, rehabilitation—fails to come into play. What research that has explored this function has been primarily interested in organizational and technical aspects of detective work. Here, I take a different approach by dissecting criminal investigations to expose their underlying structure—what they involve, how they fail, and ways they might be improved. Specific areas of interest include the functional phases of an investigation, the definition and nature of evidence, and the systemic structure of criminal investigative failures. The Gail Miller-David Milgaard murder investigation in Saskatoon, Saskatchewan, is used as a case study.

尽管犯罪学家对警务研究投入了极大的关注，但他们往往忽略了警务最重要的功能之一。侦探人员约占执法人员的16％，并通过他们的成败在警察的公众形象中发挥重要作用。鉴于警察调查员所处的门户位置，这种学术上的空缺更加令人惊讶。除非解决了犯罪并逮捕了个人，否则刑事司法系统的其余部分（检察官，辩护律师，法官，陪审团，缓刑，监狱，假释，康复）将无法发挥作用。探索该功能的研究主要对侦探工作的组织和技术方面感兴趣。这里，我通过剖析刑事调查以揭示其底层结构（涉及的内容，失败的方式以及改进方法）来采用不同的方法。关注的特定领域包括调查的功能阶段，证据的定义和性质以及刑事调查失败的系统结构。案例研究使用了萨斯喀彻温省萨斯卡通的盖尔·米勒·戴维·米尔加德谋杀案进行调查。