It is beyond peradventure that American prosecutors have ple-nary charging discretion in criminal cases; prosecutors with admissible proof beyond a reasonable doubt may nevertheless decline to seek a conviction. Such declinations are sometimes rooted in legitimate law enforcement rationales, such as the absence of sufficient enforcement resources. A prosecutor, however, might decline a meritorious prosecution simply because he or she disagrees with the applicable law or its application in the particular case. This prerogative to engage in what this Article terms “prosecutorial nullification” has been under-theorized, but raises a number of profound questions: Is prosecutorial nullification a subspecies of legitimate prosecutorial discretion, or should it be considered an extra-legal departure from established rules? What is the conceptual relation-ship of prosecutorial nullification to jury nullification and other like actions of discretion-wielding criminal justice actors? Do the unique institutional role and function of the American prosecutor provide a sufficient rationale for the power to frustrate legislative judgment and undermine (or promote) societal values and norms? This Article seeks to sharpen the definition of “prosecutorial nullification,” contextualize it within the broader conversation about discretion in the criminal process, and offer a nuanced account of its relationship with prosecutorial authority, legiti-macy, and the rule of law.