The U.S. holds more prisoners in solitary confinement than any other democratic country, according to critics of the treatment. Here, an immigrant detainee makes a call from his "segregation cell" at a detention facility in Adelanto, Calif., last November. John Moore/Getty Images hide caption
Brazil's General Superintendency of Prisons of Alagoas (SGAP) released this photo last Dec. 31 of a cat caught with contraband taped to its body at a medium-security prison in Alagoas state. AP hide caption
From 2006 to 2010, at least 148 female inmates at two California facilities had tubal ligation surgeries. Some of the surgeries took place at the Valley State Prison for Women, seen here in 2000. Gary Kazanjian/AP hide caption