Shane Bauer was one of three Americans detained in 2009 while hiking in Iraq’s Kurdish region near the Iranian border. He and Josh Fattal were held for 26 months, and Sarah Shourd — now Bauer’s wife — was held for 13 months, much of it in solitary confinement. Seven months after being freed from prison in Iran, Bauer began investigating solitary confinement in the United States. Now, in his first major article since his release for Mother Jones magazine, Bauer finds California prisoners are being held for years in isolation based on allegations they are connected to prison gangs.