This Article is the first to examine the routine—but problematic—practice of courts forgiving prosecutors for failing to disclose Brady evidence if the defendant or his lawyer knew or with due diligence could have known about the evidence. This Article begins by explaining the insidious emergence of the “due diligence” rule and catalogs how courts have defined, justified, and applied the rule since Brady v. Maryland. It argues that while the rule is not without intuitive appeal, its burden-shifting framework is troubling and suspect. The defendant due diligence rule is directly contrary to the due process and truth-seeking principles fundamental to Brady, and it ignores basic realities of adversarial criminal practice. This Article exposes and refutes several misperceptions upon which the rule rests: (1) that prosecutors can always accurately evaluate what evidence is sufficiently available through due diligence so as to justify nondisclosure; (2) that the exculpatory facts contained in a record, and in theory available to the defense, are always equal in evidentiary value to the record itself; (3) that defendants can always accurately identify legally relevant facts in their cases and can communicate effectively with their lawyers; (4) that defense lawyers have the same resources as prosecutors and, therefore, have the same ability to conduct diligent investigations; and (5) that any problems with the defendant due diligence rule can be addressed in postconviction proceedings through claims of ineffective assistance of counsel. This Article concludes by calling for elimination of the rule and the restoration of Brady’s intended framework.