The Manual on Effective Investigation and Documentation of Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment, commonly known as the Istanbul Protocol, is the first set of international guidelines for documentation of torture and its consequences. It became an official United Nations document in 1999; the most recent revision was in June 2022. The Istanbul Protocol is intended to serve as a set of international guidelines for the assessment of persons who allege torture and ill treatment, for investigating cases of alleged torture, and for reporting such findings to the judiciary and any other investigative body. Background and purpose The Manual on the Effective Investigation and Documentation of Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment contains internationally recognised standards and procedures on how to recognise and document symptoms of torture so the documentation may serve as valid evidence in court. As such, the Istanbul Protocol provides useful guidance for doctors and lawyers who want to investigate whether or not a person has been tortured and report the findings to the judiciary and any other investigative bodies. A revised, expanded version was published by the UN in June 2022. Non-binding document The Istanbul Protocol is a non-binding document. However, international law obliges governments to investigate and document incidents of torture and other forms of ill-treatment and to punish those responsible in a comprehensive, effective, prompt and impartial manner. The Istanbul Protocol is a tool for doing this. The Istanbul Protocol was drafted by more than 75 experts in law, health and human rights during three years of collective effort. While the extensive work was initiated and coordinated by the Human Rights Foundation of Turkey (HRFT) and the Physicians for Human Rights USA (PHR USA), it involved more than 40 different organisations, such as the International Rehabilitation Council for Torture Victims. The initial steps to work on a manual for the investigation and documentation of torture and other forms of ill treatment were taken at an international meeting in 1996 organised by the Turkish Medical Association and were inspired by the daily needs and practices experienced by the HRFT and the Society of Forensic Medicine Specialists in Turkey. In particular, the efforts to investigate the death of Baki Erdogan during custody became a decisive factor. Baki Erdogan died during his 11th day in custody after having been transferred to the state hospital in Turkey. The autopsy and