The United States (plaintiff) charged Booker (defendant) with drug possession with intent to distribute in violation of 21 U.S.C. § 841(a)(1). Under the statute, the conviction carried a penalty of ten years to life in prison. A jury found Booker guilty. Under the Federal Sentencing Guidelines, Booker should have been sentenced to between 210 and 262 months in prison. In a post-trial hearing, the judge found by a preponderance of the evidence that Booker possessed more drugs and was guilty of obstruction of justice. The judge sentenced Booker to 30 years in prison, and Booker appealed. The United States Court of Appeals for the First Circuit held that the sentence violated the Sixth Amendment, vacated the district court's judgment, and remanded the case for resentencing. The United States Supreme Court granted certiorari to consider whether the judge’s application of the guidelines violated the Sixth Amendment and whether the United States Sentencing Guidelines were mandatory.