Introduction
The regulation of weapons and the conduct of hostilities have traditionally been viewed through the lens of international humanitarian law (IHL), the body of law applicable during armed conflict. However, as Stuart Casey-Maslen (2015) suggests, international human rights law (IHRL) offers an 'overarching' framework that also governs the legality of weapons use. This raises important questions about the relationship between these two legal regimes. This essay will critically reflect on whether the protections offered by IHRL and IHL, when applied together, provide greater or differing safeguards. It will argue that while the concurrent application of both disciplines generally enhances protection, particularly regarding absolute prohibitions like torture and sexual violence, it also creates significant tensions and potential disadvantages, most notably in the context of weapons use and the standards governing lethal force.
The Respective Scopes of IHL and IHRL
Traditionally, IHL and IHRL were seen as operating in separate spheres. IHL, also known as the law of armed conflict, applies specifically during situations of armed conflict and aims to limit the effects of war by protecting those not participating in hostilities and regulating the means and methods of warfare (ICRC, 2016). Its core principles concerning weapons include distinction (differentiating between combatants and civilians), proportionality (ensuring an attack is not excessive in relation to the military advantage sought), and the prohibition of unnecessary suffering (banning weapons that cause superfluous injury). These principles are found in instruments like the Hague Regulations of 1907 and the Geneva Conventions of 1949 and their Additional Protocols of 1977.
In contrast, IHRL is designed to protect individuals from arbitrary actions by their own governments and applies at all times, in peace and in war. Key rights include the right to life, found in Article 6 of the International Covenant on Civil and Political Rights (ICCPR), and the absolute prohibition of torture, enshrined in Article 7 of the ICCPR. For a long time, it was assumed that during an armed conflict, IHL took precedence as the lex specialis, or the more specific law for the situation, effectively displacing the application of IHRL. However, this view has been challenged. The International Court of Justice (ICJ) in its Nuclear Weapons Advisory Opinion confirmed that the protection of the ICCPR does not cease in times of war, and that the right to life is not to be interpreted in isolation from IHL (ICJ, 1996, para 25). This establishes a model of co-application, where IHRL remains applicable, but its interpretation may be informed by the more specific rules of IHL.
Concurrent Application: Enhanced Protections and Tensions
The interaction between IHL and IHRL can be seen in several key areas, producing both complementary protections and points of friction.
Weapons Law and the Right to Life
The most significant divergence between the two regimes concerns the use of lethal force. IHL operates on the premise that in an armed conflict, combatants are legitimate targets, and their killing is not prohibited. The focus is on ensuring that attacks are proportionate and that civilians are spared as much as possible. This framework accepts that loss of life, including civilian "collateral damage," is a foreseeable consequence of military operations.
IHRL adopts a much stricter approach, derived from a law enforcement context. The right to life under IHRL, as interpreted by bodies like the European Court of Human Rights (ECtHR), means that lethal force can only be used as a last resort and must be "absolutely necessary" for the protection of persons from unlawful violence (McCann and Others v United Kingdom, 1995). This standard places a heavy burden on the state to justify any killing.
Applying these two standards together creates distinct advantages and disadvantages. The advantage is that the high threshold of IHRL provides greater protection in situations that do not meet the legal definition of an armed conflict, such as internal disturbances, riots, or counter-terrorism operations. In these 'grey zone' scenarios, applying a law enforcement paradigm prevents states from using military-style force against their own citizens. However, a significant disadvantage arises if one attempts to apply the IHRL ‘absolute necessity’ test to a battlefield. It would make conventional military operations almost impossible, as soldiers would have to justify every engagement based on a strict test of necessity rather than the IHL rules of targeting (Sassòli, 2006). Here, the lex specialis principle rightly allows IHL's more specific rules on targeting to prevail, acknowledging the unique reality of armed conflict.
The Prohibition of Torture
In the case of torture, the two legal frameworks are highly complementary and mutually reinforcing. IHL absolutely prohibits torture, cruel, and inhuman treatment of any person in custody, including prisoners of war and civilians (Geneva Conventions, 1949, Common Article 3). Similarly, IHRL contains an absolute and non-derogable prohibition on torture. Article 7 of the ICCPR and Article 3 of the European Convention on Human Rights (ECHR) permit no exceptions, even in times of national emergency.
The combined application of these regimes provides a powerful and comprehensive safeguard. The non-derogable nature of the human rights prohibition reinforces the IHL rule, leaving no legal room for any state to argue that torture is permissible in an armed conflict. Furthermore, the jurisprudence of human rights courts has extended these protections. For example, in Al-Skeini and Others v United Kingdom (2011), the ECtHR confirmed that the ECHR could apply extraterritorially to persons under the control of a state's agents abroad, such as in a detention facility in a conflict zone. This allows for an additional layer of accountability through human rights bodies, which can supplement the IHL mechanisms focused on war crimes. This convergence demonstrates a clear advantage, creating a robust and watertight legal norm against torture in all circumstances.
The Prohibition of Sexual Violence
The prohibition of sexual violence is another area where the interplay between IHRL and IHL has resulted in stronger protections. Historically, IHL was not explicit on the issue, though such acts were implicitly covered by prohibitions on assaults against personal dignity. More recently, IHL has evolved to explicitly prohibit rape and other forms of sexual violence as war crimes (Rome Statute of the International Criminal Court, 1998, Art 8).
IHRL protects against sexual violence through the right to be free from torture and inhuman or degrading treatment, as well as rights to physical integrity and privacy. By applying both frameworks, a more complete understanding of the harm is achieved. IHL contextualises sexual violence as a tactic of war, while IHRL frames it as a fundamental violation of an individual's dignity and human rights (Droege, 2007). This dual approach has strengthened international jurisprudence, with tribunals for the former Yugoslavia and Rwanda drawing on both bodies of law to prosecute these crimes. The advantage here is that the victim-centred approach of IHRL complements the conduct-focused approach of IHL, providing greater recognition of the harms suffered and reinforcing the norm against such acts.
Evaluating the Combined Framework
When viewed together, the application of both disciplines offers distinct advantages. The primary benefit is the creation of a more comprehensive protective web, filling potential gaps in IHL, especially in situations that fall below the threshold of armed conflict. IHRL provides a baseline of non-derogable protections that apply at all times, ensuring that fundamental rights are never entirely displaced. This provides different avenues for accountability, allowing for individual complaints to human rights bodies in addition to prosecutions for war crimes.
However, the disadvantages are also apparent. The main drawback is the legal uncertainty created by the overlapping and sometimes conflicting standards, particularly regarding the use of force. The tension between the IHL targeting paradigm and the IHRL ‘absolute necessity’ test is the clearest example of this. This can lead to 'legal battles about the applicable law, rather than about its application' (Melzer, 2008, p. 59). There is also a risk of inappropriately applying concepts from one field to the other, potentially militarising law enforcement or making lawful military conduct unworkable.
Conclusion
In conclusion, the protections offered by human rights law and international humanitarian law provide both greater and differing safeguards when applied together. For absolute prohibitions such as the ban on torture and sexual violence, the two regimes are complementary, reinforcing one another to create a more robust legal framework that enhances individual protection. In these areas, the combined application offers a distinct advantage with few downsides.
However, concerning the regulation of weapons and the use of lethal force, the relationship is more complex and fraught with tension. The differing standards of IHL and IHRL create potential legal conflicts and practical difficulties. While IHL remains the lex specialis for the conduct of hostilities in a clear armed conflict, IHRL provides an essential protective framework for situations outside of this context. Therefore, while Casey-Maslen's assertion that IHRL provides an "overarching framework" is correct, its interaction with IHL is not always seamless. The concurrent application of both disciplines provides a more complete, but not always perfectly coherent, system of protection that reflects the complex nature of modern conflicts.
References
- Al-Skeini and Others v United Kingdom (2011) 53 EHRR 18.
- Casey-Maslen, S. (2015) 'Weapons Under International Human Rights Law', in S. Casey-Maslen (ed.), Weapons under International Human Rights Law. Cambridge University Press.
- Droege, C. (2007) 'The Interplay between International Humanitarian Law and International Human Rights Law in Situations of Armed Conflict', Israel Law Review, 40(2), pp. 310-355.
- International Committee of the Red Cross (ICRC). (2016) International Humanitarian Law: Answers to Your Questions.
- Legality of the Threat or Use of Nuclear Weapons, Advisory Opinion [1996] ICJ Rep 226.
- McCann and Others v United Kingdom (1995) 21 EHRR 97.
- Melzer, N. (2008) Targeted Killing in International Law. Oxford University Press.
- Sassòli, M. (2006) 'The International Legal Framework for Stability Operations: When do IHL and Human Rights Law Apply?', in M. J. Matheson (ed.), Council on Foreign Relations: Conference Report. US Naval War College.
