Originally meant to be brief and exceptional, solitary confinement in U.S. prisons has become long-term and common. Prisoners in solitary spend twenty-three hours a day in featureless cells, with no visitors or human contact for years on end. They are held entirely at administrators' discretion, with no judges or juries involved. In 23/7 , legal scholar Keramet Reiter tells the history of an original "supermax," California's Pelican Bay State Prison, where extreme conditions sparked statewide hunger strikes