In the Albernaz et al. v. United States case of 1980, the Supreme Court ruled on whether or not multiple punishments for a single act were constitutional under the Double Jeopardy Clause of the Fifth Amendment. The defendants, Manuel Albernaz and others, had been convicted on two counts: conspiracy to import marijuana and conspiracy to distribute it. They argued that these convictions constituted double jeopardy as they arose from a single agreement or plan which was their only criminal intent. The court disagreed with this argument in an unanimous decision (9-0). It held that each count represented a separate statutory offense established by Congress; thus, cumulative sentences did not violate the Double Jeopardy Clause because each crime required proof of different facts and elements. The court further noted that there was no evidence suggesting Congress intended for these offenses to be punished cumulatively rather than separately. This ruling clarified how courts should interpret overlapping criminal statutes when considering issues related to double jeopardy protections - emphasizing legislative intent over common law principles like merger doctrine (which would combine similar charges into one).

In the dissenting opinion for Albernaz et al. v. United States, Justice Marshall argued that the majority's decision to allow separate punishments for conspiracy to import marijuana and conspiracy to distribute it was inconsistent with previous rulings on double jeopardy. He contended that these two charges were essentially different aspects of a single criminal agreement, not distinct offenses warranting separate penalties as per Blockburger test (which states that where the same act or transaction constitutes a violation of two distinct statutory provisions, there are two offenses only if each provision requires proof of an additional fact which the other does not). The defendants' actions in this case were part of one overarching plan; thus punishing them twice constituted double jeopardy according to him. Furthermore, he criticized Congress’s lack of clarity regarding intent about cumulative sentences under these statutes and suggested courts should interpret ambiguous sentencing laws in favor of defendants.