Source: (-0001) New York University Law Review. 80:1449-1504.Over one million defendants pass through the criminal justice system every year, yet we almost never hear from them. From the first Miranda warnings, through trial or guilty plea, and finally at sentencing, most defendants remain silent. They are spoken for by their lawyers or not at all. The criminal system treats this pervasive silencing as protective, a victory for defendants. This Article argues that this silencing is also a massive democratic and human failure. Our democracy prizes individual speech as the main antidote to governmental tyranny, yet it silences the millions of poor, socially disadvantaged individuals who directly face the coercive power of the state. Speech also has important cognitive and dignitary functions: It is through speech that defendants engage with the law, understand it, and express anger, remorse, and their acceptance or rejection of the criminal justice process. Since defendants speak so rarely, however, these speech functions too often go unfulfilled. Finally, silencing excludes defendants from the social narratives that shape the criminal justice system itself, in which society ultimately decides which collective decisions are fair and who should be punished. This Article describes the silencing phenomenon in practice and in doctrine, and identifies the many unrecognized harms that silence causes to individual defendants, to the effectiveness of the criminal justice system, and to the democratic values that underlie the process. It concludes that defendant silencing should be understood and addressed in the context of broader inquiries into the (non)adversarial and (un)democratic features of our criminal justice system (author's abstract).