OPCAT

The Optional Protocol to the Convention against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment (OPCAT) was adopted by the UN General Assembly on 18 December 2002 and entered into force on 22 June 2006. It supplements the 1984 Convention against Torture (CAT) by creating a preventive rather than reactive system: instead of investigating torture after it occurs, OPCAT establishes a regime of regular, unannounced visits to any place where people are deprived of their liberty.

OPCAT operates on a two-pillar model:

• The Subcommittee on Prevention of Torture (SPT), a 25-member international expert body based in Geneva, which conducts country visits and issues confidential reports to states.
• National Preventive Mechanisms (NPMs), which each state party must designate or create within one year of ratification. NPMs are domestic independent bodies — often ombudsman institutions, human rights commissions, or hybrid structures — empowered to inspect prisons, police lock-ups, immigration detention, psychiatric hospitals, and other custodial settings.

States parties must grant both the SPT and their NPM unrestricted access to all detention sites, the right to interview detainees privately, and access to records. The protocol applies broadly: any facility where a person cannot leave at will falls within its scope.

OPCAT is notable in international human rights law for embedding international monitoring into domestic institutions, and for its emphasis on cooperation and dialogue rather than public condemnation — SPT reports are confidential unless the state authorises publication or fails to cooperate (in which case the Committee against Torture may issue a public statement under Article 16).

Major detention-heavy states including the United States, China, Russia, India, and Saudi Arabia are not parties. Ratification has been strongest in Europe, Latin America, and parts of Africa and the Pacific. Common implementation challenges include underfunding of NPMs, lack of genuine independence, and restricted follow-up on recommendations.