Solitary confinement doesn't just sound like torture—it literally can be torture, according to the UN's lead investigator on the topic. Juan Mendez has called for a ban on solitary confinement in excess of 15 days, and a total ban on the practice when juveniles or people with mental disabilities are concerned. Speaking to a UN General Assembly human rights committee, Mendez referenced studies that found negative physical and mental effects from spending just a few days in solitary confinement.
"Segregation, isolation, separation, cellular, lockdown, Supermax, the hole, secure housing unit ... whatever the name, solitary confinement should be banned by states as a punishment or extortion technique." Mendez pointed a finger at China for keeping a woman in isolation for two of the eight years she was sentenced to serve. As for the US, he noted it's estimated that as many as 25,000 convicts are in solitary confinement, reports the BBC. (Read more solitary confinement stories.)