The non-international armed conflict between the Ukrainian government and Donetsk and Luhansk People’s Republics shows that, despite international obligations on both sides, international humanitarian law and human rights norms are rarely complied with. The recent article by Amnesty International on summary killings in Eastern Ukraine added factual and legal analysis to growing pile of data on woeful violations in Eastern Ukraine.
The recent article by Amnesty International on summary killings in Eastern Ukraine (in particular the case of Ihor Branovytsky), committed by separatist forces, added factual and legal analysis to growing pile of data on woeful violations in Eastern Ukraine. The non-international armed conflict between the Ukrainian government and Donetsk and Luhansk People’s Republics shows that, despite international obligations on both sides, international humanitarian law and human rights norms are rarely complied with. Violations are being committed on both sides of the conflict, as reported by Amnesty International and Human Rights Watch, with NGOs constantly publishing information on the misconduct (e.g., use of cluster munitions) of the Ukrainian armed forces as well.
First, international humanitarian law does not prohibit all killings – combatants can be ‘lawfully’ killed, unless they are sick, wounded, surrendered and otherwise hors de combat . However, if they are detained  – ‘in power of the enemy’ – they must be treated humanely. The standards of treatment are included both in treaties  and customary law  – if it might be questionable whether armed groups are bound by the former, they are definitely bound by the latter. In addition to humane treatment, law provides with specific prohibitions of ‘wilful killing’ as a grave breach (war crime) of Geneva Conventions , or ‘summary’ or ‘arbitrary executions’ in human rights law , which still applies even in situations of armed conflict .
Hopefully, Ukraine is a party to the Additional Protocol II, which covers the situations of non-international armed conflict, as well as all the Geneva Conventions and many human rights law treaties, including International Covenant on Civil and Political Rights. If one is to assume that law applies territorially, then the prohibitions cover all de jure territory of Ukraine. On the other hand, since the government does not control the territory, the unlawful conduct can be attributed only to the armed group (or a government, provided there is effective  or overall control  over that armed group) – and there is evidence that prove misconduct by separatist forces. Moreover, since LPR and DPR are claiming to be state-like entities, it would be rather useful for them to comply with international law – if not for a benevolent image, at least to avoid prosecution later.
It seems quite unrealistic to expect that now, in a situation of almost non-existent rule of law, the perpetrators – the ones who wield power there at the moment – would face justice. This was exactly the attitude of Tutsis before ICTR and Gacaca courts, or victims of war in former Yugoslavia before the international tribunal was established. Notwithstanding all the shortcomings of contemporary international criminal regime, it can still be efficient – especially if the countries express their willingness to cooperate. In case of Ukrainian conflict, this can be done by ratifying the Rome Statute of International Criminal Court, which territorial jurisdiction would definitely cover the violations in Eastern Ukraine as well. The ICC Statute includes war crimes of killing persons protected in armed conflict (such as detainees)  as well as crimes involving command responsibility for not punishing their subordinates . Even without ICC, the Ukrainian judicial system may be quite well-equipped for such trials, as far as it is able and willing to do so.
In the end, these crimes have already been committed. Now it is up to commanders and leaders, both military and civilian, to prevent further violations, enforce penal sanctions for the perpetrators and investigate these and other cases. The inability – or unwillingness – to assume their responsibility now may result in criminal liability for war crimes not only for the immediate commanders, but many more people, up to the highest positions. As international tribunals since Nuremberg have shown, the list of perpetrators includes not only those who pull the trigger, but those who order or even turn a blind eye. Justice knows no ranks.
1. Geneva Conventions I-IV, Art. 3
2. Detention by armed groups in non-international armed conflict is another issue, not strictly relevant here. For more information, see ICRC Website, Detention in non-international armed conflict: The ICRC's work on strengthening legal protection. URL: https://www.icrc.org/eng/what-we-do/other-activities/development-ihl/strengthening-legal-protection-ihl-detention.htm
3. Geneva Conventions I-IV, Art. 3, Additional Protocol to Geneva Conventions (II), Art. 4, Art. 5
4. For reference see ICRC Customary Law Study, Rule 87. URL: https://www.icrc.org/customary-ihl/eng/docs/v1_rul_rule87
5. Using the analogy of Geneva Convention I, Art. 50
6. E.g., International Covenant on Civil and Political Rights, Art. 6 (1)
7. UN Human Rights Committee, General Comment 31, para. 11. URL: http://www.refworld.org/docid/478b26ae2.html
8. As used in Nicaragua v. USA case, ICJ, 1986
9. As stated in Tadić case, AC, ICTY, 1999
10. ICC Statute, Art. 8 (2)(c)(i)
11. ICC Statute, Art. 28