EXECUTIVE SUMMARY 1. This report presents the findings of the comprehensive human rights assessment of the situation of detainees at the Guantánamo Bay detention facility, conducted by the Office for Democratic Institutions and Human Rights (ODIHR) of the Organization for Security and Co-operation in Europe (OSCE) from 2012 to 2015. This assessment was carried out in line with ODIHR’s mandate to support the OSCE participating States in developing and implementing human rights-compliant measures to prevent and counter terrorism and to monitor the implementation of their human dimension commitments. 2. The human rights assessment carried out by ODIHR consisted of in-depth research, two fact-finding missions to the United Sates in February and September 2014, and a series of interviews with a broad range of stakeholders. In September 2014, ODIHR held eight interviews with relevant US officials from the Departments of State, Defense and Justice and the Presidential Administration, including senior officials involved in the proceedings before the military commissions. ODIHR also met with 14 representatives of nongovernmental organizations, 25 military and civilian lawyers representing Guantánamo detainees in past and current cases before the military commissions, habeas corpus proceedings or before the Periodic Review Board (PRB), five former detainees as well as medical and legal experts working on Guantánamo. 3. ODIHR appreciates the constructive and result-oriented co-operation with all US officials involved throughout the whole process of producing this report. However, ODIHR’s experts had not been granted private meetings with detainees currently held at Guantánamo. As an alternative method of obtaining the views of current detainees, the Office submitted written questions to several of them. ODIHR received one response included in this report, the contents of which, apart from the heading, had been entirely redacted by the authorities before being shared with ODIHR. 4. The report analyses the compliance with international human rights standards of the detention, conditions of confinement and treatment of detainees at Guantánamo (Part 1) and the proceedings before the military commissions (Part 2). It also explores the challenges related to the closure of the detention facility, accountability for alleged human rights violations both at Guantánamo and in the Central Intelligence Agency (CIA) Rendition, Detention and Interrogation (RDI) programme as well as the right to redress in cases of victims of arbitrary detention, torture and/or ill-treatment, addressing in that respect the human rights obligations of not only the United States but also other concerned OSCE participating States (Part 3). The report covers relevant developments up until 31 August 2015. 5. The analysis and recommendations formulated in this report rely on relevant OSCE commitments, international human rights law and standards and, as applicable, international humanitarian law. It focuses primarily on international treaties that have either been signed or ratified by the United States as well as on customary international law. It also refers to soft law principles and opinions of authoritative bodies providing guidance on the interpretation of international law. Domestic standards are also mentioned 7