ICRC Humanitarian Law and Policy Blog

The ICRC’s 2005 study on customary international humanitarian law – along with the free, public database launched five years later – arrived at a moment when the legal landscape of armed conflict was rapidly shifting. Mandated by the 26th International Conference of the Red Cross and Red Crescent, the study set out to map the customary rules governing contemporary warfare by systematically analyzing global state practice and opinio juris. Twenty years on, with more than 130 armed conflicts active worldwide, reassessing the study’s methodological contributions, its evidence base, and its impact on the regulation of both international and non-international armed conflicts offers a timely lens on how customary IHL continues to underpin protections for people affected by war. In this post, ICRC Legal Adviser Claudia Maritano and members of the British Red Cross-ICRC customary IHL research team reflect on how the study’s rigorous methodology, global scope, and identification of 161 customary rules helped clarify gaps left by treaties, especially in non-international armed conflicts, and strengthen the practical application of IHL.

Large-scale armed conflicts consistently sever the systems that sustain civilian life, leaving populations without essential services or access to basic goods. International humanitarian law (IHL) sets out clear obligations for states to anticipate these foreseeable humanitarian needs and to ensure that impartial relief can reach affected communities swiftly and safely. Yet from customs hurdles to restrictive regulatory frameworks, many of the barriers to life-saving assistance are rooted not in conflict itself, but in peacetime choices. In this post, ICRC Legal Adviser Ellen Policinski examines how states can proactively shape legal, administrative, and logistical systems that enable, rather than obstruct, humanitarian relief in moments of crisis. She underscores that meeting IHL obligations requires advance preparation – from easing import restrictions to ensuring postal and customs exemptions – so that when conflict erupts, assistance can move without avoidable delay.

The environmental toll of armed conflict is neither insignificant nor fleeting: it contaminates water, soil, and air, erodes ecosystems, undermines livelihoods, and burdens public health long after the fighting stops. The damage both mirrors and magnifies humanitarian crises, from Gaza’s mountains of debris to Ukraine’s flood-borne pollutants, to Sudan’s industrial contamination. Compounded by the impacts of the climate crisis, these environmental challenges only deepen the vulnerabilities of those affected by conflict. Understanding and addressing the interwoven impacts of conflict and the environment is essential for global climate, nature, pollution and sustainable development efforts, and to ensure that people can live and thrive in a healthy, secure and resilient environment. In this post, part of the War, Law and the Environment series, the UNEP Disasters and Conflicts Branch reflects on its decades of work helping countries address these challenges, charting a path from emergency response to long-term recovery. Through science-based assessments, practical guidance, and strategic partnerships, UNEP is equipping states to address the toxic legacies of war, restore ecosystems, and build resilience into the reconstruction process. Recent UN resolutions, including UNEA’s 2024 consensus decision, underscore growing political recognition that protecting the environment in armed conflict is integral to peace and recovery. What emerges is a vision of environmental response not as an afterthought to war, but as a cornerstone of recovery, and an entry point to build back greener, fairer, and stronger in the shadow of destruction.

Five States Parties to the Anti-Personnel Mine Ban Convention have recently submitted instruments of withdrawal, citing national security and military necessity, while at least one other has taken steps to “suspend” the Convention. These developments raise important questions about whether anti-personnel mines retain any meaningful military utility in contemporary conflict. In this post, Erik Tollefsen, Head of the ICRC Weapon Contamination Unit and Pete Evans, Head of the ICRC Unit for Arms Carriers and Prevention examine this question from an operational perspective. They argue that advances in technology and the realities of modern warfare have significantly reduced the military relevance of anti-personnel mines, while their humanitarian consequences remain severe. They outline why some of the most frequently cited justifications – border security, the supposed benefits of “smart” mines, or perceived low cost – no longer withstand scrutiny, and why renewed interest in these weapons risks reversing decades of progress. The authors call on states to base decisions on rigorous, transparent assessments of current military relevance weighed against humanitarian and legal obligations. In a security environment defined by rapid innovation, they conclude that, now as at the Convention’s adoption 30 years ago, anti-personnel mines have no place on the modern battlefield – and that reaffirming the norm against their use is more urgent than ever.

More than 200 million people live today in contested territories – places where the authority of the state is challenged outright and armed groups exercise full or fluid control. This number has risen by 30 million since 2021. These are not distant statistics; each figure represents a person living in the shadow of competing powers, making difficult choices in an almost impossible environment. How do people navigate the presence of multiple, often competing, armed actors? Is dignity found in defiance, or safety in uneasy compliance? How do families secure food, water or medical care when neither the state nor armed groups are able or willing to provide basic services? And, crucially, what can humanitarian actors do to better protect and assist those caught in these fractured landscapes? In this post, and drawing on recently published research in Cameroon, Iraq and the Philippines, Arjun Claire, Senior Policy Adviser at the ICRC, and Matthew Bamber-Zryd, the ICRC’s Adviser on Armed Groups, offer five insights to help strengthen humanitarian responses in contested territories – insights rooted in the lived realities of the people who navigate them every day.

Restrictions on movement and access to medical supplies have become an often-unseen threat to health care in today’s armed conflicts. Even where hospitals are not attacked, the quiet tightening of supply routes can deprive them of the medicines, equipment, and basic services they need to function. In this post, ICRC Legal Advisers Supriya Rao and Alexander Breitegger outline what the obligation to protect medical facilities means in practice, from allowing the passage of medical consignments to enabling essential services like power and water. They also describe how concerns about dual-use risks must be balanced against humanitarian needs, and highlight ongoing work under the Global IHL Initiative to identify good practices that help keep hospitals operating even in the most difficult conditions.

As artificial intelligence (AI) begins to shape decisions about who is detained in armed conflict and how detention facilities are managed, questions once reserved for science fiction are now urgent matters of law and ethics. The drive to harness data and optimize efficiency risks displacing human judgment from one of the most sensitive areas of warfare: deprivation of liberty. In doing so, AI could strip detainees of what remains of their humanity, reducing them to data points and undermining the core humanitarian guarantees that the Geneva Conventions were designed to protect. In this post, Terry Hackett, ICRC’s Head of the Persons Deprived of Liberty Unit, and Alexis Comninos, ICRC’s Thematic Legal Adviser, explore how the use of AI in detention operations intersects with international humanitarian law (IHL), and why humane treatment must remain a human-centered endeavor. Drawing on the ICRC’s recent recommendations to the UN Secretary-General, they argue that while IHL does not oppose innovation, it sets the moral and legal boundaries that ensure technological progress does not come at the cost of human dignity.

When people go missing in war, their absence lingers far beyond the battlefield – splintering families, deepening social divides, and haunting political transitions. Yet amid this grief, the families of the missing often become unlikely peacebuilders: their search for truth draws them across old front lines, transforming pain into connection and personal loss into a collective force for reconciliation. In this post, Jill Stockwell, Simon Robins, and Martina Zaccaro explore how families of the missing – through shared advocacy and dialogue – can reshape divided societies. Drawing on ICRC research from Bosnia and Herzegovina, Cyprus, and Nepal, they show how families who once faced each other as enemies now work side by side, using their moral authority and lived experience to foster empathy, resist manipulation, and model the very reconciliation peace processes often fail to achieve.

When wars end, peace rarely begins overnight. It’s built, slowly and painstakingly, through acts that restore a sense of humanity where it was once suspended. Among these, how a society treats people it detains may seem peripheral, yet it can determine whether trust survives long enough for peace to take root. Humane detention, often overshadowed by more visible aspects of conflict recovery, is in fact one of the earliest and most concrete tests of readiness for peace. Each act of respect for law and dignity – registering a detainee, allowing a family visit, providing medical care, or releasing a prisoner when the reason for detention has ceased – helps reduce the harm that fuels revenge and instead preserves the fragile threads of trust that can bind divided societies. In this post, Terry Hackett, ICRC’s Head of the Persons Deprived of Liberty Unit, and Audrey Purcell-O’Dwyer, ICRC’s Legal Adviser with the Global Initiative on IHL, show how compliance with international humanitarian law (IHL) in detention – while not a direct path to peace – can serve as a legal and moral bridge towards it, one rooted in dignity, accountability, and the quiet rebuilding of trust. By limiting suffering and safeguarding dignity, it helps prevent conflicts from eroding the institutions and confidence that societies need to recover.

Picture a potential future armed conflict: missiles and drones crowding the skies, uncrewed vehicles rolling across borders, and governments scrambling to coordinate their defences. Their conclusion: Every citizen is needed. Some collect and relay information about the approaching enemy into an artificial intelligence (AI) platform that supports military decision-making. Reservists join the ranks of the armed forces. Computer experts choose to contribute by conducting cyber operations aimed at disrupting military operations, sowing chaos among the civilian population, and harming the enemy’s economy. As the militaries on both sides rely heavily on digital communication, connectivity, and AI, the armed forces call on tech companies to provide cybersecurity services, computing power and digital communication networks. In this post, Tilman Rodenhäuser, Samit D’Cunha, and Laurent Gisel from the ICRC, Anna Rosalie Greipl from the Academy, and Professor Marco Roscini from the University of Westminster (and former Swiss IHL Chair at the Geneva Academy) present five key risks for civilians, along with the obligations of both civilians and states, related to the involvement of civilians in information and communication technology (ICT) activities in armed conflict.