From Complicity to Due Diligence: When Do States Incur Responsibility for Their Involvement in Serious International Wrongdoing?

Abstract

The article considers different modes of State involvement in serious violations of international law and the legal criteria for unlawful contributions. Giving special attention to participation below the level of complicity – when a State contributes to serious violations without possessing positive knowledge – the author considers primary rules of international law that prohibit indirect participation, such as the duty to respect and ensure fundamental human rights. The article argues in favour of a risk-based ex ante responsibility in order to prevent cooperation between States which violate fundamental legal norms of the international community. Accordingly, States incur responsibility for indirect participation if they do not exercise the necessary diligence to prevent such violations. Though due diligence is usually referred to when States fail to intervene in cases of third party abuse, it applies a fortiori in cases of active contributions. While the article concentrates on serious human rights violations, it also refers to other fields of international law, including breaches of international humanitarian law. By specifying the legal parameters of due diligence as a general principle it thus contributes to the scholarly debate on the content of due diligence in international law more generally.