From secret stingray devices that can pinpoint a suspect’s location, to advanced forensic DNA-analysis tools, to recidivism risk statistic software—the use of privately developed criminal justice technologies is growing. So too is a concomitant pattern of trade secret assertion surrounding these technologies. This Article charts the role of private law secrecy in shielding criminal justice activities, demonstrating that such secrecy is pervasive, problematic, and ultimately unnecessary for the production of well-designed criminal justice tools. This Article makes three contributions to the existing literature. First, the Article establishes that trade secrecy now permeates American criminal justice, shielding privately developed criminal justice technologies from vigorous cross-examination and review. Second, the Article argues that private law secrecy surrounding the inner workings—or even the existence—of these criminal justice technologies imposes potentially unconstitutional harms on individual defendants and significant practical harms on both the criminal justice system and the development of well- designed criminal justice technology. Third, the Article brings the extensive literature on innovation policy to bear on the production of privately developed criminal justice technologies, demonstrating that trade secrecy is not essential to either the existence or operation of those technologies. The Article proposes alternative innovation policies that the government, as both a funder of research and the primary purchaser of criminal justice technologies, is uniquely well-positioned to implement.