A Denver Post review of Denver Police Department data on confidential informants found that only about 40 percent of those used last year had proved themselves reliable in previous cases. The rest were first-time informants, whose fitness for assignments is typically established by their criminal activity or drug use and their access to other criminals. Denver police say 90 percent of their informants have a criminal record. Informants who give bad information may be removed from service, but they’re unlikely to face stiffer penalties unless they commit a crime while working for police. Discipline for officers who mishandle cases involving informants is rare. “Because the use of informants is so unregulated, the public almost never learns about it until something goes terribly wrong,” said law Prof. Alexandra Natapoff of Loyola Law School in Los Angeles.
Police and prosecutors say the problems that come with reliance on informants are outweighed by the benefits. Informants provide the backbone for hundreds of drug investigations each year. With the ability to move in and out of the criminal world, informants, who often are criminals working for cash or deals from authorities, provide investigators with information they couldn’t obtain otherwise. “The bottom line is they have access that we do not,” said Denver police Capt. Steven Carter. “They know people that have access that we will likely never have. Without that, there are a lot of things that will go undetected until it’s too late.” The International Association of Chiefs of Police has a model policy for how departments should handle informants. The Post compared it with those of seven of the state’s largest law-enforcement agencies. Each required background checks for informants and commander approval. But policies varied regarding whom police use and how they’re used during investigations.