"[5] Opponents of the measure sued, and on December 27, 1994, U.S. District Judge Michael Robert Hogan issued a preliminary injunction forbidding the state from enforcing the statute,[6] then, on August 3, 1995, declared the law unconstitutional under the Equal Protection Clause.

[3] Members of Congress next sought to have the federal government prosecute physicians obeying the new Oregon law, and DEA Administrator Thomas A. Constantine told them that he had authority to do so under the Controlled Substances Act (CSA).

[10] After Senator Ashcroft became United States Attorney General in 2001, he secured a memorandum from the Office of Legal Counsel concluding that physician-assisted suicide violates the CSA.

[19][20] The federal government's petition for a writ for certiorari was granted and one hour of oral arguments were heard on October 5, 2005, with Paul Clement, the Solicitor General of the United States, personally appearing.

[16] The Court did not dispute the power of the federal government to regulate drugs, but it disagreed that the statute in place empowered the attorney general to overrule state laws on the appropriate use of medications allowed.

[16] Even without granting any agency deference, the Attorney General's interpretation was reasonable because, Scalia argued: "If the term 'legitimate medical purpose' has any meaning, it surely excludes the prescription of drugs to produce death.

Thomas made clear that, although he still believes the CSA is not empowered by the Constitution's Interstate Commerce Clause to regulate purely intrastate conduct, if it were, the Attorney General's interpretation of the statute would be reasonable.