A/HRC/42/CRP.1 when it is strictly necessary and in accordance with the principle of proportionality. It should be restricted to situations of last resort, i.e. as a response to an imminent threat of death or serious injury.939 Use of force that does not comply with those principles and results in death amounts to an arbitrary deprivation of life.940 Under international humanitarian law, when – within the context of an armed conflict – a party to the conflict intentionally kills a civilian, it amounts to wilful killing or, in a non-international conflict, to murder.941 Murder is considered a war crime.942 613. The Group of Experts has reasonable grounds to believe that the Yemeni armed forces, on 13 November 2018, used excessive force in shooting with live fire at peaceful demonstrators who were apparently not representing any threat to life or serious injury. Individuals may be held criminally responsible for war crimes for these acts. 614. Enforced disappearance is prohibited by international human rights law and international humanitarian law, notably as a violation of the prohibition of arbitrary deprivation of liberty and possibly of the prohibition of torture. 943 International human rights law and international humanitarian law also prohibit arbitrary detention.944 Considered as arbitrary are deprivations of liberty that are contrary to international law provisions, mostly those relating to the right to a fair trial or other procedural guarantees, as well as detentions based on the exercise of fundamental freedoms. Depriving a person of the right to a fair trial may be considered a war crime in a non-international conflict.945 Torture and other cruel, inhuman or degrading treatment are also strictly prohibited under both international human rights law and international humanitarian law, and may lead to individual criminal responsibility for war crimes. 946 615. The Group of Experts has reasonable grounds to believe that Saudi Arabia and the Government of Yemen are responsible for enforced disappearance and arbitrary detention of individuals perceived as political opponents. In one case, the Group has reasonable grounds to believe that Saudi Arabia and the Government of Yemen are responsible for torture and ill-treatment, which may lead to criminal responsibility for the war crimes of torture and cruel or inhuman treatment. VII. Gender analysis and gender-based violence 1. Introduction 616. The armed conflict has affected women, girls, men and boys differently due to underlying inequalities across communities in Yemen. Yemeni society was already patriarchal and many women and girls, particularly those from minority or rural communities, lived in profoundly unequal and dangerous situations. The actions of the parties to the conflict have exacerbated this situation by exploiting gender norms in furtherance of their objectives. This has also affected gains in women and girls’ empowerment that had been made prior to the conflict, serving to stall, and in some ways, reverse prior achievements. New vulnerabilities to gender-based violence have emerged from displacement, poverty, and indiscriminate violence. The already limited support 939 Code of Conduct for Law Enforcement Officials, 1979, Art. 2-3; Principles 5, 9, 13 and 14, Basic Principles on the Use of Force and Firearms by Law Enforcement Officials, 1990. 940 Art. 6 ICCPR. 941 Art. 3 common to the Geneva Conventions, Art. 4(2)(a) Additional Protocol II; See ICRC Study on customary IHL, rule 89. 942 Art. 8 2.(c)(i) Rome Statute. 943 Art. 9 ICCPR and Art 1 International Convention for the Protection of All Persons from Enforced Disappearance (CED); see ICRC Study on customary IHL, rule 98. 944 Art. 9 and 14 ICCPR; Art. 3 common to the Geneva Conventions and Art. 4 Additional Protocol II; See ICRC Study on customary IHL, rule 99. 945 See ICRC Study on customary IHL, rule 100. 946 Article 7 ICCPR, See Convention against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment; Art. 3 common to the Geneva Conventions, art. 4 Additional Protocol II, See ICRC Study on customary IHL, rule 90. 147