A/HRC/37/42 amount to grave breaches of the Geneva Convention relative to the Protection of Civilian Persons in Time of War (Fourth Geneva Convention), hence to war crimes. 7 In addition, protected persons shall only be detained only in the Occupied Palestinian Territory and the non-respect of this rule violates the prohibition of forcible transfer; another grave breach of the Fourth Geneva Convention and a war crime. 8 III. Arbitrary detention in the Occupied Palestinian Territory A. Introduction 6. The Working Group has identified five legal categories relating to arbitrary detention: (a) when there is no legal basis for the deprivation of liberty (category 1), (b) when the deprivation of liberty results from the exercise of fundamental freedoms, (c) when the violations of norms relating to the right to a fair trial are of such gravity as to give the deprivation of liberty an arbitrary character, (d) when migrants are subjected to prolonged administrative custody without the possibility of administrative or judicial review or remedy, and (e) when the deprivation of liberty reflects discrimination, notably based on birth, national, ethnic or social origin, language, religion and political or other opinion. 9 7. Based on those categories, and in view of the cases monitored by OHCHR during the reporting period, the present report is divided into two parts describing two sets of factors perpetuating arbitrary detention in the Occupied Palestinian Territory. In the first part, the High Commissioner examines cases of detention without apparent or legitimate grounds, or where the right to a fair trial is not guaranteed (categories 1 and 3). In the second part, the High Commissioner examines cases where individuals have been detained for exercising their fundamental freedoms (category 2). 8. Although of particular relevance to the present context, arbitrary detention on discriminatory grounds (category 5) is not addressed separately in this report, as it is likely to apply to most cases described therein. The Working Group has notably invoked detention on discriminatory grounds in its conclusions pertaining to several cases of detention of Palestinians by Israel. 10 The Secretary-General has also noted how the application of two different legal systems in the same territory, on the sole basis of nationality or origin, is inherently discriminatory and undermines the right to a fair trial.11 B. Detention without grounds or fair trial guarantees 9. This section focuses on cases of detention that are likely to be arbitrary due to the absence of any legal basis justifying the detention, or where there are no prospects for a fair trial. Given the frequent invocation of vague security grounds and the use of secret evidence in the Occupied Palestinian Territory, it is often impossible to determine whether the detention is based on a legitimate ground. The practice of administrative detention is also addressed in this section. 1. Detention without legitimate grounds or legal basis 10. To be in conformity with international human rights law, any deprivation of liberty must have a legal basis. Where no reasonable ground is invoked, the detention is considered as arbitrary. Arbitrary detention is practised by Israel, the State of Palestine and the authorities in Gaza. 7 8 9 10 11 Ibid., art. 147; Rome Statute of the International Criminal Court, art. 8 (2) (a) (vi). Fourth Geneva Convention, arts. 49 (1), 76 and 147; Rome Statute, art. 8 (2) (a) (vii). Methods of work of the Working Group on Arbitrary Detention (A/HRC/36/38). See opinions No. 31/2017, No. 15/2016 and No. 13/2016. See A/HRC/34/38, para. 40. 3