In the 1985 case of Skipper v. South Carolina, the United States Supreme Court ruled in favor of Johnny Skipper, who had been sentenced to death for a crime he committed. The court held that it was unconstitutional for the trial judge to refuse to admit evidence regarding Skipper's good behavior during his time in jail awaiting trial as part of his defense against capital punishment. The jury should have been allowed to consider this information when deciding whether or not to impose a death sentence. This decision was based on the Eighth and Fourteenth Amendments which require that sentencing juries be able to fully consider all relevant mitigating factors before imposing capital punishment.

In the dissenting opinion for Skipper v. South Carolina, Justice Powell argued that the majority's decision expanded the scope of mitigating evidence in capital sentencing hearings beyond what was intended by previous rulings and legislation. He expressed concern that this expansion could lead to confusion and inconsistency in future cases. Moreover, he disagreed with the majority's interpretation of "character" as including behavior during incarceration awaiting trial, arguing instead that it should be limited to long-term patterns of behavior prior to arrest. Furthermore, he contended that even if such evidence were admissible under some circumstances, Skipper had not shown a likelihood of his good prison conduct continuing indefinitely into the future - an essential requirement for it to have any mitigating value at all according to him.