In Bifulco v. United States, the Supreme Court ruled that a federal court cannot impose special parole terms on individuals convicted under the Comprehensive Drug Abuse Prevention and Control Act of 1970. The case involved two defendants who were found guilty of participating in an illegal drug conspiracy and sentenced to prison along with special parole terms. They appealed their sentences, arguing that the law did not authorize such additional penalties for their specific offense. The government countered by pointing out that another section of the same law allowed for these types of sentences in similar cases involving drug offenses. However, after examining both sections closely, the Supreme Court sided with the defendants and held that Congress had not intended to allow courts to add special parole terms onto regular prison sentences for this particular crime.

In the dissenting opinion for Bifulco v. United States, Justice Rehnquist disagreed with the majority's interpretation of 21 U.S.C. § 848(b)(2), which pertains to sentencing in drug-related cases. He argued that Congress intended for a special parole term to be mandatory after imprisonment and fines have been imposed under this law, not discretionary as the majority concluded. The language of the statute was clear and unambiguous in his view; it stated that violators "shall" be sentenced to a special parole term on top of their prison sentence and fine, indicating an obligation rather than an option. Furthermore, he pointed out inconsistencies between different parts of Section 848 if interpreted according to the majority’s viewpoint – one part would require a special parole term while another wouldn’t - leading him to believe that such an interpretation could not have been what Congress intended when drafting this legislation.