Mistretta (petitioner) and another were indicted on three counts in a cocaine sale. Mistretta moved to have the promulgated Guidelines ruled unconstitutional on the grounds that the Sentencing Commission was constituted in violation of the established doctrine of separation of powers, and that Congress delegated excessive authority to the Commission to structure the Guidelines. The District Court rejected petitioner's delegation argument on the ground that, despite the language of the statute, the Sentencing Commission 'should be judicially characterized as having Executive Branch status,' and that the Guidelines are similar to substantive rules promulgated by other agencies. The court also rejected petitioner's claim that the Act is unconstitutional because it requires Article III federal judges to serve on the Commission. The court stated, however, that its opinion 'does not imply that I have no serious doubts about some parts of the Sentencing Guidelines and the legality of their anticipated operation.' Petitioner then pleaded guilty to the first count of his indictment (conspiracy and agreement to distribute cocaine, in violation of 21 U.S.C. §§ 846 and 841(b)(1)(B)). The Government thereupon moved to dismiss the remaining counts. Petitioner was sentenced under the Guidelines to 18 months' imprisonment, to be followed by a 3-year term of supervised release. The court also imposed a $1,000 fine and a $50 special assessment. Petitioner filed a notice of appeal to the Eighth Circuit, but both petitioner and the United States, pursuant to this Court's Rule 18, petitioned for certiorari before judgment. Because of the 'imperative public importance' of the issue, as prescribed by the Rule, and because of the disarray among the Federal District Courts, the Supreme Court granted those petitions.