The aim of this article is to reflect upon accountability under international law through the framework of a specific example. The Turkel Commission is a public commission of inquiry appointed by the Government of Israel. It issued its second and final report, which addresses Israel’s mechanisms for investigating violations of international law according to the laws of war, in February 2013. The Report primarily focuses on International Humanitarian Law (IHL) but also attends to International Human Rights Law (IHRL). The duty to investigate under international law is an evolving process because treaty law lacks detail, particularly regarding the manner of conducting an investigation. Under IHRL that duty has been enriched by the jurisprudence of regional human rights courts and soft law. Under IHL duty (which is even sparser in detail) it has been aided by state practice and the jurisprudence of international tribunals. The Turkel Report is the first major study on the duty to investigate and it informs much of the analysis of this article. The article provides a descriptive review of the Report and a critical discussion of the way this current national development offers a meaningful contribution to the development of the obligation imposed by international law to investigate alleged violations.