The United Nations has called for a global ban on solitary confinement, highlighting America's torture practices.
"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," UN Special Rapporteur on torture Juan Méndez told the General Assembly.
"Solitary confinement is a harsh measure which is contrary to rehabilitation, the aim of the penitentiary system."
Méndez noted that in the United States an estimated 20,000 to 25,000 individuals are being held in isolation.
He said the use of prolonged or indefinite solitary confinement has increased, especially in the "war on terror'' and in dealing with threats to national security.