This Essay is the third part of a larger project examining the potential role of professional discipline in the regulation and supervision of prosecutors’ charging decisions. The first two parts of the project argued that courts have both the authority and the ability to exercise effective disciplinary review of charging decisions through the adoption of ethics rules and their enforcement in the disciplinary process. This Essay takes the next step in the project, considering the nature of rules that courts might adopt, by exploring potential rules targeting two improprieties: arbitrary and capricious charging decisions, and discriminatory charging decisions.