In United States v. Dack, 747 F.2d 1172, 1176 n. 5 (7th Cir.1984) , the defendant subpoenaed the prosecutor to testify concerning the Supreme Court's holding in a recent case. See id. The Court held that the district court properly quashed the subpoena because the defendant could have easily made the same point by entering the United States Reports into evidence. See id.