Money motivates and regulates criminal process. Conscious of adjudication costs, prosecutors incentivize guilty pleas with the prospect of a “trial penalty”—harsher post-trial sentences. Budgetary considerations motivate revenue-generating enforcement policies and asset forfeitures by law enforcement. States also charge defendants directly for nearly every criminal justice expense through mandatory fees, which can burden decisions to exercise rights. Additionally, defendants can pay for optional advantages. Right-to-counsel doctrine protects the right to pay for more and better legal assistance than the state is obligated to provide. Paying bail yields pretrial liberty. Diversion programs, for a fee, can supplant ordinary prosecution. Some defendants can choose their sentence—a fine or jail. But these opportunities are not available to all; their costs need not match one’s ability to pay. To examine roles and rules of money in criminal process, this paper considers the case for an optional criminal trial fee. Defendants who pay it would directly cover public litigation costs, which would leave the state indifferent, as a budgetary matter, between trials and guilty pleas. In return, defendants would get a penalty-free trial limited to the terms of a proffered plea bargain. The fee proves a useful device because its rationale and effects accord with entrenched precedents and policies, not least in how it extends the justice system’s differential treatment based on wealth. Yet the trial fee also promises positive effects. It would reduce prosecutors’ most-criticized bargaining tactics—excessively harsh trial penalties—without undermining bargaining’s important secondary functions, enlisting informants to cooperate and rewarding defendants who accept responsibility for their crimes. And even a modest increase in fee-financed trials would yield other benefits, such as citizen participation in applying criminal law and supervising government officials, and more data about “the shadow of trial” in which bargaining takes place