Susan Greene is the winner of the February Sidney Award for The Gray Box: An Investigative Look at Solitary Confinement, a story and documentary video about the agony of solitary confinement in American prisons, published in the Dart Society Reports.

Some 80,000 prisoners are housed in isolation on any given day in U.S. prisons, typically in cells no bigger than a pair of queen-sized mattresses.

Solitary confinement was invented by Quaker prison reformers in the 1800s. They hoped that keeping prisoners in strict isolation would encourage them to reflect and repent. However, it rapidly became clear that instead of spurring reform, solitary confinement was literally driving inmates insane. “[Solitary confinement] devours the victims incessantly and unmercifully,” Alexis de Tocqueville wrote of a New York prison in the 1820s. “It does not reform, it kills.”The practice was banned as inhumane by the late 1880s, only to reappear in 1983 as a response to prison violence.

Over the course of years of reporting, Greene was able to piece together the lives of some of the most isolated people in the world. She corresponded with prisoners in solitary and interviewed others after they were released. She found that survivors of solitary confinement are ill-equipped to rejoin society after prolonged isolation.

Read my interview with Susan Greene at The Backstory.

The Sidney Award is given once a month in recognition of an outstanding work of socially conscious journalism.