Human Rights vs Complementarity: the Iraq war, the UK, & the International Criminal Court

On 20th March 2003 a US-led coalition, which included the UK, invaded Iraq initiating an international armed conflict. By 7th April 2003, UK forces had occupied the city of Basra and surrounding areas. Nearly two decades later the role of the UK armed forces in Iraq is still under the scrutiny of the International Criminal Court. Incidents arising out of the UK occupation of southern Iraq were submitted to the Office of the Prosecutor (OTP or Office) by those who believed members of the UK forces committed war crimes within the Court’s jurisdiction. On 9th December 2020, the ICC Prosecutor published the Final Report on the “Situation in Iraq/UK”, concerning crimes potentially committed by the UK armed forces, classified as war crimes within the jurisdiction of the Court. Due to the principle of complementarity, the OTP closed the preliminary examination without seeking authorisation to initiate an investigation. This case could be considered as a milestone in the evolution of the concept of complementarity in international criminal law. The deep analysis of the national proceedings, in terms of the willingness of the competent UK authorities to carry out the relevant investigations or prosecutions under article 17(2), is a trailblazer of the so-called complementarity assessment. The principles, as well as the methodology adopted in the Iraq/UK Final Report, represents a fundamental step forward, that will influence the ICC Prosecutor on future cases involving questions of pre-existing national legal proceedings and the whole process of complementarity evaluations.