As a result of Russia’s invasion of Ukraine in February 2022, we are sitting at a crossroads where one path further weakens the prohibition of the use of force and another helps restore its integrity. In this context, this article argues it is imperative that we take all available steps to reinforce the prohibition, and that holding President Putin to account for the crime of aggression holds the key in this regard. The article explains why it is necessary to establish an ad hoc international tribunal to prosecute crimes of aggression committed against Ukraine given the International Criminal Court lacks jurisdiction over any crime of aggression involving a State not party to the Rome Statute, the impossibility of amending the Statute in this instance, and the impediments that will stand in the way of a successful domestic prosecution of the crime of aggression, including immunities enjoyed by those most responsible. Finally, the article addresses the principal objections to the proposed tribunal including its cost (which is overstated and pales in comparison to the mounting cost of the ongoing conflict); its supposed redundancy given efforts to prosecute other serious international crimes committed in Ukraine (which undersells the challenge of holding leaders to account and discounts the value of separately prosecuting aggression); and the concern that the tribunal would represent selective justice (which overlooks the fact that a prosecution of the leaders of one of the world’s most powerful States would help end, rather than exacerbate, international criminal justice’s selectivity problem).

The Fourth Geneva Convention provides the main protection regime for civilians in the hands of a party to an international armed conflict. Yet its application is limited to non-nationals, and conditional upon states’ belligerent and legal relations. This article historicises and problematises the so-called nationality requirement for the treatment and protection of civilians. The significance of nationality for international humanitarian law has changed considerably since the late nineteenth century. The complex delineation of civilian protected persons under the Fourth Geneva Convention was, therefore, not inevitable. The article challenges the common perception of the treaty as a humanitarian achievement designed to safeguard innocent and vulnerable civilians. This detailed study of nationality provides insights into the changing perception of civilians as war victims and the role of international humanitarian law in protecting them.

Alexander Gilder’s Stabilization and Human Security in UN Peace Operations is a concise and accessible welcome addition to the academic literature on peacekeeping missions. The book analyses in detail the notion of stabilisation and its relation to the idea that peacekeeping operations can enhance human security. For many reasons, which are explored below, this book should be read by any legal or non-legal scholar interested in recent trends in peacekeeping operations. Legal works on peacekeeping operations, especially book-length endeavours, suffer mainly from two problems: first, it is difficult to explore peacekeeping operations from a purely legal perspective since there is scant law available on peacekeeping. At the risk of oversimplification, we should bear in mind that peacekeeping operations are not part of the original design of the Charter of the United Nations (UN), but rather, they are mainly governed by the specific mandate adopted by the UN Security Council (SC). Since the UNSC is a political organ with broad discretion and few available checks and balances, one could provocatively argue that the law on peacekeeping is merely the political will of the UNSC translated into a series of resolutions that share a very indeterminate and fluid common legal content. ¹ The second obstacle in analysing peacekeeping operations from a legal perspective is the staggering bulk of practice generated by the UNSC in this field. In trying to reduce all this practice to law—something that is in the DNA of international lawyers accustomed to working with rules generated by practice—it is very difficult to differentiate between such drastically different missions that are all labelled as peacekeeping. As one of my old mentors once told me, the UNSC has ‘watered down’ the idea of peacekeeping to the extent that today everything or nothing under the UNSC egis can be considered to be a peacekeeping mission depending on how flexible we interpret the boundaries of the notion of peacekeeping to be.

This article discusses whether computer data constitutes an ‘object’, in the meaning of this term under international humanitarian law (IHL). After providing background on what is meant by ‘computer data’, and on the significance of any determination whether computer data constitutes an ‘object’ for the purposes of IHL, the article proceeds to consider the meaning of the term ‘object’ as found in the First Additional Protocol to the Geneva Conventions (API). Recourse is made to the customary rules of treaty interpretation while focusing on both the English and French versions of API. The ordinary meaning of the term ‘object’ in its context in API solely connotes material things, thus excluding computer data. Moreover, recourse to the object and purpose of API, or to so-called ‘evolutionary’ interpretation, does not lead to a different conclusion. Considering the importance of customary international law for states non-parties to API, and for the purposes of non-international armed conflicts, the article proceeds to analyse whether computer data constitutes an ‘object’ for the purposes of custom. The article analyses the development of the term ‘object’ in legal discourse over the past century in determining what states intended this term to mean, and finds that here, too, states considered ‘objects’ in the context of IHL to be material things. It also explains that there is no apparent trend among states as to whether data constitutes an ‘object’, whereas the paucity of official government statements is far from the necessary volume for it to carry particular legal significance.

This is a correction to: Hanna Bourgeois, Patryk I Labuda, When May UN Peacekeepers Use Lethal Force to Protect Civilians? Reconciling Threats to Civilians, Imminence, and the Right to Life, Journal of Conflict and Security Law, 2022, https://doi.org/10.1093/jcsl/krac027

The protection of civilians (PoC) concept remains contested twenty-three years after the first PoC mandate. Current PoC frameworks used by the United Nations (UN) do not assist with determining applicable legal standards. They lead the UN down an unsustainable path that risks diminishing political support for PoC, especially within intense conflicts and following well-documented protection failures. With ever-rising expectations from communities under protection, the UN’s ‘Three Tiers of PoC Action’, and the complexity and dilution of PoC mandates under a whole-of-mission approach, it becomes challenging to determine what missions must do to protect individuals. Undertaking a major re-evaluation of PoC, this article charts the progression of PoC mandates drawing on examples from several missions drawing out the diverse nature of PoC and subsequent activities. The article then argues that current definitions and practical applications of PoC have cast the net too wide, presented uncertainties, and leave PoC open to attack from Member States amidst a political climate of weakened support for collective security action. Instead, the discussion must shift towards a concise and shared understanding of what protection mandates entail for UN peace operations. The article suggests how PoC can be reconceptualised to distinguish a narrow and easily communicated minimum obligation to be placed on UN peacekeepers.

The obligation to legally review weapons, means and methods of warfare has been identified by the Group of Governmental Experts on Emerging Technologies in the Area of Lethal Autonomous Weapons Systems as one of its Guiding Principles. Despite calls to share practical measures and processes to undertake this review, national practice remains opaque and fragmented. This article describes the traditional weapons review process and explains why this process may need to be modified to adequately evaluate autonomous weapon systems (AWS). It uses three case studies of fictional AWS in various stages of development and acquisition to demonstrate how existing review processes can be adapted for the review of AWS. This article shows the utility of these reviews for ensuring compliance of AWS with existing legal requirements, thereby also demonstrating the suitability of existing law to regulate the use of this novel technology in warfare.

This is a correction to: Anna Liguori, Overlap Between Complicity and Positive Obligations: What Advantages in Resorting to Positive Obligations in Case of Partnered Operations?, Journal of Conflict and Security Law, Volume 27, Issue 2, Summer 2022, Pages 229–252, https://doi.org/10.1093/jcsl/krac008

The book under review contains sixteen sections, covering the experiences of the Royal Air Force’s (RAF) Reaper operations in Afghanistan, Iraq and Syria. Lee’s contribution is not specifically dealing with ethics, morality or just war issues surrounding the UK’s RAF Reaper programme. This book includes unprecedented research access to the Reaper squadrons at RAF Waddington in Lincolnshire and Creech Air Force Base in Nevada, USA. In this review, I will focus on how the book’s argument, as exemplified in selected passages, posits a ‘controlled’ narrative of the UK’s RAF Reaper programme, attempting to ward off any legal or ethical conundrums with the use of drone strikes as a targeted killing tool for counter-terrorism purposes. While Lee’s book does not cover the legal issues surrounding drone strikes, he includes incidences where some of the RAF Reaper crew had to determine legality before targeting. In particular, Lee touches on ‘just war’ via the incidents which put forward for the first-time interesting material for assessment by legal and ethics academics—and practitioners.

Peace mediation as a form of peaceful settlement of disputes has evolved significantly in the past 20 years, moving away from an informal process between parties towards a more structured undertaking rooted in norms and values of international law. Sitting between Chapter VI and Chapter VII of the UN Charter, mediation is an underexplored aspect of the collective security regime in international law. Surprisingly little attention has been paid to the role of the UN Security Council (UNSC) and the exercise of legal authority under Chapter VII in shaping mediation mandates. This article addresses this gap by developing a theoretical framework for understanding the role of UNSC in the construction of security in the context of peacemaking. Using the mandate of the Office of the Special Envoy for Yemen as a case study, the article traces the progression of the mediation mandate a set out in the UNSC resolutions, interrogating the shift in discourse from UN support for an inclusive political transition into a narrower focus on hard security and the international response to the threat of terrorism. Through this analysis the article demonstrates how the place of UNSC within the Charter system allows for a gradual securitisation of the peace mediation process at the expense of inclusive approaches. At a time when consensus on collective security appears to be weakening the role of the UNSC in constructing and responding to global threats is of significant interest to the future of Charter-based international peace and security.