In a 7-to-2 decision, the Supreme Court held that McKinney's suit stated a reasonable claim that, if proven, could be grounds for relief under the Eighth Amendment prohibition of cruel and unusual punishment. Justice Byron White, in the majority opinion, rejected the government's argument that the "deliberate indifference" test established by the Court in Wilson (which held that withholding medical care from prisoners only violated the Eighth Amendment if it was done with "deliberate indifference" to serious health risks) only applied to current medical conditions. If McKinney could prove that the second-hand smoke posed a serious threat to his future health and that the prison officials had deliberately ignored that threat, White wrote, McKinney would be entitled to relief. Access audio recording of oral argument and case information here.
https://www.oyez.org/cases/1992/91-1958