Abstract: The American penal system is a system of massive, racially unjust incarceration. It is also, to quote the U.S. Supreme Court, a "system of pleas." The latter drives the former, as coercive plea bargaining makes it possible for the state to do two things that are otherwise hard to pull off at once: increase convictions and sentence lengths. Mass incarceration is a predictable result. But while plea bargaining is intensely coercive when leveraged against individuals, the system of pleas has a structural weak point. That Achilles' heel is exposed once we see people facing prosecution not as isolated individuals but rather as a potentially collective community of power. Organized to act together, this community has unique resources. Most notably, they have the power to say "not guilty" when asked "how do you plead?" If done together, this simple but profound act of resistance would bring the penal system to a halt. Courts and prosecutors simply do not have the resources to sustain mass incarceration while affording everyone accused of a crime the constitutionally guaranteed right to a trial. This fact is what makes plea bargaining so essential to mass incarceration in the first place. Plea bargaining unions, with their implicit power to threaten plea bargaining strikes, thus hold a potentially transformative power--a decarceral power, a democratic power--that arises from the penal system's massive overextension. Susan Barton, a formerly incarcerated organizer, floated this idea in the pages of The New York Times with Michelle Alexander one decade ago. In the years since, it has never received focused academic attention and has seen only sporadic and isolated attempts at implementation. This Essay aims to conceptualize and test the limits of Burton's idea, examining both its promise and its hurdles while marking key questions for future exploration.