prisons

Martin Sostre on Feb. 12, 1976 — the same week he was released from prison after he was granted executive clemency by the governor of New York. Vic DeLucia/The New York Post via Getty Images hide caption

This Jan. 28, 2016 file photo shows a solitary confinement cell at New York City's Riker's Island jail. On March 31, 2016, a federal judge approved a sweeping plan to reduce solitary confinement in New York state prisons. Bebeto Matthews/AP hide caption

Keith Cole is one of the Texas inmates in the federal lawsuit challenging extreme heat in Texas prisons. John Burnett/NPR hide caption

Supporters of Egypt's ousted President Mohammed Morsi, a Muslim Brotherhood leader, chant slogans against the Egyptian military during a trial in which they were charged with violence in Alexandria, Egypt, on March 29, 2014. Thousands of Muslim Brotherhood supporters have been jailed by the current government. A former prisoner tells NPR he saw some turn to ISIS in prison. Heba Khamis/AP hide caption

Many federal inmates have access to email but defense attorneys say they don't trust it, because prosecutors have used those emails as evidence in court. Patrick George/Ikon Images/Getty Images hide caption

Federal regulators will vote on capping the cost of phone calls from prison, which are far more expensive than ordinary calls. iStockphoto hide caption

Inmates Ted Stancil (from left), Steven Bass and Christopher Peeples, with their welding Instructor Jeremy Worley (standing in center) at Walker State Prison in Georgia. The inmates are working toward a welding certificate. Susanna Capelouto/WABE hide caption

The plaintiffs in the case are inmates at Pelican Bay State Prison near Crescent City, Calif. "In the most severe cases," Juan Mendez says, indefinite solitary confinement — like that practiced at Pelican Bay — "can even be considered torture." Rich Pedroncelli/AP hide caption

Nicklas Trujeque in his solitary confinement cell in New Mexico State Penitentiary. Inmates spend 23 hours a day in these cells, with a one-hour period in an open cell outside. According to the New Mexico ACLU, until recent state reforms, the average length of stay for an inmate here was around three years. Natasha Haverty/For NPR hide caption

A part of Eastern State Penitentiary in Philadelphia is shown in 2008. The penitentiary opened in 1829, closed in 1971, and then historic preservationists reopened it to the public for tours in 1994. Matt Rourke/AP hide caption

Latandra Ellington, 36, was serving time for tax fraud at Lowell Correctional Institution when she died. Florida Department of Corrections hide caption