IV. THE WORKING GROUP ON ENFORCED OR INVOLUNTARY DISAPPEARANCES The United Nations General Assembly has devoted particular attention to this odious phenomenon on many occasions. In 1978, in its resolution 33/173, it expressed concern over reports from various parts of the world relating to enforced or involuntary disappearances of persons. It requested the United Nations Commission on Human Rights to consider the question and to make appropriate recommendations. By resolution 20 (XXXVI) of 29 February 1980, the Commission on Human Rights decided to establish a working group of five independent experts to examine questions relevant to enforced or involuntary disappearances of persons. Since then, the mandate of the Working Group has been regularly renewed. A. Definition of enforced disappearance In accordance with the definition contained in the preamble to the Declaration, the Working Group operates on the basis that enforced disappearances are considered as such only if perpetrated by State actors or by private individuals or organized groups, for example, paramilitary groups,5 acting on behalf of, or with the support, direct or indirect, consent or acquiescence of State authorities. Therefore, the Working Group does not admit cases attributed to perpetrators that do not fall under these categories, such as non-State-sponsored terrorist or insurgent movements fighting the Government on its own territory. This distinction is based of the principle that States have the obligation to investigate and sanction acts similar in nature to enforced disappearance when committed by non-State actors. The Working Group maintains that the State’s responsibility for enforced disappearances continues irrespective of changes of Government, even if the new Government shows greater respect for human rights than the Government in power at the time the disappearances occurred. Nevertheless, when studying the situation of enforced disappearances in a particular country or examining the phenomenon generally, the Working Group considers information on all kinds of disappearances to be relevant to a proper evaluation. The Working Group does not deal with disappearances in the context of international armed conflicts, in view of the competence of the “Paramilitary groups” are organized groups that are effectively armed, trained or supported by the regular army. 5 11