The federal government (plaintiff) prosecuted Korrigan Brown (defendant) on several counts relating to the armed robbery of two stores, in violation of 18 U.S.C. §§ 924 and 1951. Neither statute required the government to prove a defendant's sanity as an element of the offense. Brown admitted the robberies but pleaded not guilty by reason of insanity. Two mental health experts testified that Brown suffered from bipolar disorder, also known as manic-depressive illness. The judge denied Brown's request for a jury instruction that a conviction required proof, beyond a reasonable doubt, that he was not insane when he robbed the stores. Instead, the judge instructed the jury on the insanity defense provided by 18 U.S.C. § 17, as amended by the Insanity Defense Reform Act of 1984 (IDRA). The judge told the jurors that § 17 required Brown to establish, by clear and convincing evidence, the high probability that at the time of the charged offense, a severe mental disease or defect prevented him from appreciating the nature and quality or wrongfulness of his act. The jury found Brown guilty on all counts. On appeal to the Eleventh Circuit Court of Appeals, Brown argued that § 17(b) deprived him of due process by relieving the government's obligation to prove every element of the charged offenses.