Customary international law

Customary international law arises where states follow a sufficiently general and consistent practice because they believe they are legally obliged to do so (*opinio juris*). It may coexist with treaties and can bind states that are not parties to a relevant convention, subject to limited objections for persistent objectors. In Swiss practice, customary international law is relevant for interpreting international obligations, immunities, human rights and humanitarian law. Its content is often identified through state conduct, diplomatic positions, judgments and authoritative international materials.