Certain obligations under international law are aimed at safeguarding the rights of beneficiaries potentially affected by state measures or by actions of third parties approved, acquiesced or endorsed by the state. These rules, which we call prophylactic rules, are fundamental for the realisation of the protected rights. The question of when exactly international responsibility arises from non-compliance with prophylactic rules is subject to debate, in part because these rules require processes that ensure the preservation of associated rights.
In this article, we use the obligation to conduct free, prior, and informed consultation, a prophylactic rule aimed at protecting collective rights of Indigenous Peoples, to dissect the consequences of non-compliance with this type of rules. We explain that compliance with these rules carries a presumption of protection of associated rights and its breach the opposite: a presumption of breach. We conclude by arguing that Prophylactic International Law is an expanding phenomenon motivated by the growth of actors impacted, and subjects protected by international law. In this context, the experience of the Inter-American Human Rights system can serve as a source of inspiration to address the doctrinal and normative debates around the enforcement of prophylactic rules.