In 2017, the International Committee of the Red Cross published an updated Commentary on the Second Geneva Convention. One question left unanswered by the new Commentary is the relationship between international humanitarian law and other international treaties applicable to the maritime domain, such as the U.N. Convention on the Law of the Sea (UNCLOS) and treaties adopted by the International Maritime Organization (IMO). The Second Geneva Convention establishes a legal framework for the humane treatment and protection of victims of armed conflict at sea—the wounded, sick and shipwrecked. There are circumstances, however, in which the belligerents do not have the capability or capacity to conduct adequate search and rescue operations after an engagement. In such cases, the Second Geneva Convention allows the parties to the conflict to supplement their search and recovery efforts by requesting assistance from neutral merchant vessels. However, there is no obligation on the part of the belligerents to do so, nor is there an obligation on the part of a neutral to respond to such a request. Nonetheless, customary international law recognizes an affirmative obligation of mariners to render assistance to persons in distress at sea to the extent that they can do so without serious danger to their ship, crew, or passengers. A number of IMO treaties codify this long-standing custom, as does UNCLOS.
Still, numerous legal questions remain. For example, does the outbreak of hostilities terminate or suspend the applicability of these maritime conventions or do they remain in effect, in part or in their entirety, during an armed conflict at sea? Do different rules apply between parties to the conflict and parties to the conflict and neutral powers? Are parties to the conflict and neutral powers nevertheless bound during an armed conflict at sea by the provisions of the maritime conventions that reflect customary international law? This article analyzes these questions in light of applicable international law and U.S. state practice. The article concludes that the peacetime duty to render assistance to mariners in distress at sea remains in effect during an armed conflict as a treaty obligation and/or as a matter of customary international law in three circumstances: (1) neutral parties must render assistance to other neutral parties; (2) neutral parties must render assistance to belligerent parties upon request or sua sponte; and (3) belligerent parties must render assistance to neutral parties.