The use of mechanical restraint is a common practice in psychiatric care, often defended by medical necessity but seldom questioned from a human rights perspective. The purpose of this thesis has been to investigate under which circumstances mechanical restraint by bed through belt fixation could amount to torture and other cruel, inhuman or degrading treatment or punishment. Persons with psychosocial disabilities are in a particularly vulnerable situation and as the International Convention on the Rights of Persons with Disabilities (CRPD) is the most comprehensive rights framework for this group, it has been discussed whether the CRPD sets out additional safeguards in relation to restraint.  A legal doctrinal approach is the basic methodology used in order to outline the current international and European legal framework on torture and other ill-treatment and disability rights. A survivor-controlled research methodology has been applied and to amplify other voices of persons with firsthand experience of being mechanically restrained, interviews have been conducted with persons from Sweden and Spain. Healthcare professionals have also been interviewed. A feminist perspective on the law is applied.  Different international conventions and bodies of the United Nations have diverse interpretations on what acts or omissions that amount to torture and other cruel, inhuman or degrading treatment or punishment, although there is an aim and will to streamline the conventions. It is clear that the use of mechanical restraint can create such intense mental or physical suffering required to reach the common criterion of seriousness. However, some people do not experience the required levels of suffering for it to be considered torture, meaning that it might not amount to torture but rather other ill-treatment. The threshold for being considered torture according to the Convention against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment (UNCAT) seems to be somewhat higher than that of the International Covenant on Civil and Political Rights (ICCPR) and the European Convention of Human Rights (ECHR). In this thesis it was found that the most critical element for this is the requirement of intent. Intent can however be implied under certain circumstances if the practice is of discriminatory nature. If a person has a psychosocial disability, intent might be presumed if States do not provide appropriate health care. In the case of girls and women, intent might also be presumed since they seem to have a higher risk of getting restrained for unlawful reasons.  The main conclusion in this thesis is that mechanical restraint by bed through belt fixation could amount to torture or other cruel, inhuman or degrading treatment or punishment according to the UNCAT, ICCPR and ECHR.