"Guantánamo is a place of arbitrariness and abuse, a site where torture and ill-treatment was rampant and remains institutionalised, where the rule of law is effectively suspended, and where justice is denied," the experts said in a press release on Monday.
They said the covid-19 pandemic further exacerbates health vulnerabilities for the increasingly elderly prison population.
"The very existence of this facility is a disgrace for the United States and the international community as a whole. Guantánamo should have been closed a long time ago," the UN experts said on the 19th anniversary of its establishment.
In 2003, the facility was holding 700 prisoners. Nineteen years later, 40 detainees still remain but only nine of them have been charged with or convicted of crimes.
UN experts have consistently demanded the dismissal of the Military Commissions and the closure of the detention facility at Guantánamo Bay, holding them incompatible with the United States’ obligations under international law.
"We must not forget these detainees, who have been subjected to torture or victims of comparable trauma, and still languish in Guantánamo, in a virtual legal limbo, outside the reach of the constitutional judicial system of the United States," they said.
"The prolonged and indefinite detention of individuals, who have not been convicted of any crime by a competent and independent judicial authority operating under due process of law, is arbitrary and constitutes a form of cruel, inhuman and degrading treatment or even torture," they added.
Military Commissions are still undergoing pre-trial proceedings on motions to suppress evidence resulting from torture. Trials are not expected anytime soon, as such proceedings are likely to last several years, leaving the defendants indefinitely held. Six have long been cleared for transfer and one has recently been cleared for release through national security processes. All remain imprisoned.
"The Military Commissions violate the requirements of impartiality, independence and non-discrimination and should never have been used in the manner in which they were deployed at Guantánamo. These individuals should receive a fair and public hearing by competent, independent and impartial civilian court previously established by law," the experts said.
"We appeal to U.S. authorities to prosecute, in full compliance with human rights law, the individuals held at Guantánamo Bay or, alternatively, immediately release or repatriate them while respecting the principle of non-refoulement," they stated.
The experts said the US must uphold its international legal obligations, conduct prompt and impartial investigations of alleged human rights violations and provide redress and rehabilitation to those who have endured prolonged arbitrary detention or any form of torture or ill-treatment.