An inmate has the right to sue prison officials if he is forced to share his cell with a smoker.
The Supreme Court says it's cruel and unusual punishment.
By a 7-2 vote, the court ruled Friday that a Nevada prisoner need not show that he already has been harmed by exposure to secondary smoke to get to court. Rather, the risk of becoming ill is sufficient.
The Environmental Protection Agency said earlier this year that second-hand cigarette smoke is a serious public health hazard to non-smokers.
The ruling also has broader implications for criminal defendants. The court made clear that risks to future health, rather than only actually sustained injuries, could form the basis of constitutional claims.
The court majority, led by Justice Byron R. White, rejected arguments that the Eighth Amendment prohibition against cruel and unusual punishment cannot be based on the future effects of involuntary exposure to tobacco smoke.
Justices Clarence Thomas and Antonin Scalia dissented, objecting to the court's allowing constitutional protection for a "mere risk of injury."
On the court, Chief Justice William H. Rehnquist smokes cigarettes. Thomas smokes cigars, and Scalia smokes cigarettes and a pipe.
Friday's ruling allows a lawsuit by convicted murderer William McKinney to go forward, although, White said, "the prisoner must show that the risk of which he complains is not one that today's society chooses to tolerate."
Nevada prison officials, since the 1986 case began, have separated smoking and non-smoking prisoners.
In other cases, the court ruled:
The use of a government interpreter for a deaf child at a Catholic school does not violate the constitutional requirement of separation church and state. Story, 4A.
States may be forced to give refunds to retired federal employees who paid what were later declared to be unconstitutional taxes. Story, 4A.
_ Information from Reuters and Times files was used in this report.