The unanimous ruling upholds a federal law that requires state prisons to accommodate inmate religions. Prisoners in Ohio -- including a witch and a Satan worshipper -- had claimed they were denied access to religious literature, ceremonial items and time to worship.
Justice Ruth Bader Ginsburg defended the 2000 statute, which was intended to protect the rights of prisoners. She said the law did not present any unconstitutional government promotion of religion.
Opponents of the law had argued that inmate requests for particular diets, special haircuts or religious symbols could make it harder to manage prisons.
The law says states that receive federal money must accommodate prisoners' religious beliefs, unless wardens can show that the accommodation would be disruptive. The court left open the door for a future challenge, on grounds that the law could overburden prisons.