Justice Manual § 9-11.233

In United States v. Williams, 112 S.Ct. 1735 (1992), the Supreme Court held that the Federal courts' supervisory powers over the grand jury did not include the power to make a rule allowing the dismissal of an otherwise valid indictment where the prosecutor failed to introduce substantial exculpatory evidence to a grand jury. It is the policy of the Department of Justice, however, that when a prosecutor conducting a grand jury inquiry is personally aware of substantial evidence that directly negates the guilt of a subject of the investigation, the prosecutor must present or otherwise disclose such evidence to the grand jury before seeking an indictment against such a person. While a failure to follow the Department's policy should not result in dismissal of an indictment, appellate courts may refer violations of the policy to the Office of Professional Responsibility for review.