About the Optional Protocol to the Convention against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment The Optional Protocol to the Convention against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment (OPCAT) is an international human rights treaty designed to strengthen the protection of people deprived of their liberty. Its adoption by the United Nations General Assembly in 2002 reflected a consensus among the international community that people deprived of their liberty are particularly vulnerable to ill-treatment and that efforts to combat such ill-treatment should focus on prevention. OPCAT embodies the idea that prevention of ill-treatment in detention can best be achieved by a system of independent, regular visits to all places of detention. Such visits monitor the treatment of and conditions for detainees. OPCAT entered into force in June 2006. States that ratify OPCAT are required to designate a ‘national preventive mechanism’ (NPM). This is a body or group of bodies that regularly examine conditions of detention and the treatment of detainees, make recommendations, and comment on existing or draft legislation with the aim of improving treatment and conditions in detention. In order to carry out its monitoring role effectively, an NPM must: 1 • be independent of government and the institutions it monitors; • be sufficiently resourced to perform its role; and • have personnel with the necessary expertise and who are sufficiently diverse to represent the community in which it operates. Additionally, the NPM must have the power to: • access all places of detention (including those operated by private providers); • conduct interviews in private with detainees and other relevant people; • choose which places it wants to visit and who it wishes to interview; • access information about the number of people deprived of their liberty, the number of places of detention and their location; and • access information about the treatment of and conditions for detainees. The NPM must also liaise with the United Nations Subcommittee on Prevention of Torture and other Cruel, Inhuman or Degrading Treatment or Punishment (SPT), an international body established by OPCAT with both operational functions (visiting places of detention in states parties and making recommendations regarding the protection of detainees from ill-treatment) and advisory functions (providing assistance and training to states parties and NPMs). The SPT is made up of 25 independent and impartial experts from around the world and publishes an annual report on its activities.1 All annual reports, including the most recent 11th annual report which covers the work carried out by the SPT in 2017, are available on the website of the Office of the High Commissioner for Human Rights, https://tbinternet.ohchr.org/_layouts/ treatybodyexternal/TBSearch.aspx?Lang=en&TreatyID=12&DocTypeID=27, accessed 9 July 2018.