Complementarity and cooperation are essential principles of the International Criminal Court (ICC), which ideally aims to work with, rather than replace or oppose, national authorities investigating and prosecuting international crimes committed on their territory. Current ICC Prosecutor Karim Khan has emphasised these principles more than his predecessors, leading to the Office of the Prosecutor’s (OTP) disengagement in some country situations while still overseeing cooperation agreements and other forms of engagement with national authorities. The International Federation for Human Rights (FIDH) has closely followed this shift in tactics of the OTP and delivers its current insights and recommendations in this Q&A.
26 April 2024. The principles of complementarity and cooperation are deeply enshrined in the founding texts of the International Criminal Court (ICC). Under the principle of complementarity, the ICC can only intervene when national judicial authorities are unable or unwilling to genuinely investigate and prosecute perpetrators of international crimes. The ICC Statute also clearly sets obligations for States Parties to cooperate with the Court.
While previous ICC Prosecutors have reportedly worked towards improved cooperation between the ICC and States, and towards a more effective application of the principle of complementarity, since taking office in 2021, ICC Prosecutor Karim Khan expressed an increased emphasis on cooperation with States. He also presented his new approach to complementarity and cooperation, justifying a series of decisions relating in particular to the closing of preliminary examinations, of investigations, de-prioritisation of certain cases, and the adoption of several cooperation agreements with national authorities.
In October 2023, the Office of the Prosecutor (OTP) launched a public consultation on a first ever Policy on Complementarity and Cooperation (Policy), emphasising the need for the ICC to act as a “hub” within a network of accountability efforts, rather than positioning itself at the “apex” of the Rome Statute system. FIDH commented on the Draft Policy back in November 2023. Today, the OTP published its Policy.
This Q&A explores the new approach, commenting on Karim Khan’s decisions relating to cooperation and complementarity taken so far, analysing the new Policy, and the potential impacts of this new approach on victims and justice processes.
1 - Why are complementarity and cooperation so important?
2 - What is new about ICC Prosecutor Khan’s approach to cooperation and complementarity?
3 - How has the Prosecutor’s new approach impacted preliminary examinations and investigations so far?
4 - Which preliminary examinations and investigations were closed under the Prosecutor’s new approach, and why?
5 - What does cooperation between the OTP and States Parties look like in practice?
6 - What is the aim of the OTP’s new Policy on Complementarity and Cooperation?
7 - Are there concerns about double standards in the support provided by the OTP to national authorities?
8 - What is the role of civil society envisaged by the OTP Policy and how can meaningful engagement be concretely improved?
9 - What is FIDH’s overall take on the ICC OTP’s approach to complementarity and cooperation, and what concerns remain?
10 - Any insights into how the OTP plans to implement and advance the new Policy in 2024 and beyond?
1 - Why are complementarity and cooperation so important?
The Rome Statute’s principles of cooperation and complementarity are vital for the ICC’s functioning. Cooperation (Articles 86 to 88) requires ICC States Parties to support the Court in its investigations and prosecutions, including essential activities like the arrest and surrender of suspects. Complementarity (Preamble, Articles 1 and 17) establishes that the ICC acts as a court of last resort, intervening only when national jurisdictions are unable or unwilling to investigate and prosecute perpetrators of Rome Statute crimes. These principles are crucial for the effectiveness of the ICC, ensuring that it works alongside national legal systems and judicial authorities rather than replacing them.
FIDH has consistently advocated for improved cooperation of states and intergovernmental organisations (including the UN Security Council) with the Court, by supporting the ICC in its investigation and prosecution work, providing the Court with the necessary means to meaningfully fulfil its mandate, and implementing its decisions, be it with the enforcement of arrest warrants, sentences or reparation orders. FIDH has also emphasised the need for a more proactive role of the ICC in cooperating with national judicial authorities and supporting concretely national justice efforts to hold perpetrators of international crimes to account, in application of the principle of complementarity.
2 - What is new about ICC Prosecutor Khan’s approach to cooperation and complementarity?
While previous ICC Prosecutors have prioritised cooperation with states and other stakeholders, and tried to implement a “positive approach” to complementarity, by encouraging and supporting national authorities in their primary obligation to investigate and prosecute international crimes, Prosecutor Khan’s approach marks a shift from his predecessors’. His approach focuses on enhanced cooperation with states and declares increasing his efforts towards a more proactive implementation of the principle of complementarity, aimed at using ICC resources to encourage states to fulfil their obligations under international law. This new approach has seemingly led to the closure of multiple preliminary examinations and investigations for various reasons, often grounded in the principle of complementarity, which prioritises investigations and prosecutions of international crimes by national jurisdictions over the ICC. Prosecutor Khan is also aiming to institutionalise his approach with the first ever ICC OTP’s Policy on Complementarity Cooperation which goes far beyond previously adopted ICC prosecutorial strategies.
3 - How has the Prosecutor’s new approach impacted preliminary examinations and investigations so far?
According to Prosecutor Khan, “implementation of completion strategies can give tangible expression to the core principles of cooperation and complementarity that are at the heart of the Rome Statute system.” The Prosecutor has closed four investigations (Georgia, Central African Republic (CAR) II, Kenya, and Uganda) since he took office in 2021, providing some details on his completion strategies, but these strategies still require substantive development and public clarification. His predecessors did not close any. In line with this approach, the Prosecutor also recently announced his hope of completing investigative activities in Libya by the end of 2025.
He has additionally closed three preliminary examinations (PEs) since 2021 (Colombia, Bolivia, and Guinea), with what FIDH and member organisations have criticised for lacking proper justification and transparency (see Q 4 below). Meanwhile his predecessor, Prosecutor Fatou Bensouda was the first to close PEs, closing five PEs between 2012 and 2021 (Gabonese Republic, Honduras, Republic of Korea, Comoros, and UK/Iraq). FIDH previously identified the OTP’s practices, as well as achievements and opportunities for it to improve its working methods, transparency, and communication with civil society at the preliminary examination stage in its paper published in September 2021.
4 - Which preliminary examinations and investigations were closed under the Prosecutor’s new approach, and why?
The ICC Prosecutor’s new approach on complementarity and cooperation has ostensibly led to the closure of the following six PEs and investigations, in order to increase support and emphasis on genuine national proceedings - though the genuineness of these domestic actions remains questionable:
1. Colombia (PE concluded on 28 October 2021): 17 years after the PE of crimes against humanity and war crimes in Colombia, the ICC Prosecutor decided not to initiate an investigation, indicating implementing the principle of complementarity, and to conclude a Cooperation Agreement with the Colombian Government. The OTP determined that national authorities were actively investigating and prosecuting crimes within the ICC’s jurisdiction. On 27 April 2022, FIDH and the Colectivo de Abogados José Alvear Restrepo (CAJAR) filed a request for review and annulment of the Prosecutor’s decision not to open an investigation, since there was still a systematic absence of investigations into the highest perpetrators of Rome Statute crimes, and asked for a proper explanation of the reasons behind this decision. In July 2022, ICC judges decided to review the request, and while they rejected the annulment request, they ordered the Prosecutor to justify closing the PE, which he did more than two years after his decision, in a final report on the situation, on 30 November 2023. Regrettably, many questions remain regarding the prospect for accountability for atrocities in Colombia, and complementarity remains elusive.
2. Guinea (PE closed on 29 September 2022): 13 years after the crimes were committed, and the ICC PE was opened, the trial of the 28 September 2009 Conakry stadium massacre began in Guinea on 28 September 2022, charging 11 individuals for their alleged involvement in the violence, where 156-200 people were reportedly killed or disappeared and 109 women suffered rape or sexual violence. The ICC Prosecutor attended the opening of the trial and announced the closure of the PE in Guinea, concluding that national authorities in Guinea were not inactive, unwilling, nor unable to genuinely investigate and prosecute alleged crimes committed at the Conakry stadium. The Prosecutor called it a day of “complementarity in action” which also included the signing of a Memorandum of Understanding with Guinea to strengthen future cooperation. The trial in Guinea continues. FIDH has been supporting and representing victims in this trial, also calling for the meaningful implementation of the principle of complementarity.
3. Georgia (investigation concluded on 16 December 2022): The Georgia investigation was opened in 2016 and resulted in three arrest warrants for alleged war crimes during the 2008 Russia-Georgia conflict, involving the unlawful detention, mistreatment, and use of ethnically Georgian civilians as bargaining tools in South Ossetia. Georgian civil society, including FIDH’s member organisation Human Rights Center (formerly Human Rights Information and Documentation Center (HRIDC)), welcomed the arrest warrants, and urged the ICC Prosecutor to actively pursue the investigation beyond the three pending arrest warrants, so that high-ranking officials of the Russian Federation could also be held accountable, and for the Court to dedicate the necessary resources and adopt meaningful prosecutorial and outreach strategies for the Georgia investigation. The Prosecutor did not provide a clear reason for concluding the investigation in December 2022, but hinted at considerations like limitations in resources and the principle of complementarity. He explained his new “dynamic approach to complementarity” with “two-way cooperation”, aimed at supporting domestic courts in prosecuting cases, marking a shift towards a more collaborative relationship with national authorities, including sharing resources and expertise, and engaging with civil society in Georgia. The ICC suspects remain at large, and regretfully there has been no domestic accountability for these crimes. Two-way cooperation with national authorities and engagement with civil society is not visible, and complementarity in practice therefore remains an unrealised ideal in Georgia.
4. CAR II (investigation concluded on 16 December 2022): In 2014, the CAR II investigation was opened into alleged war crimes and crimes against humanity since July 2002, by both Séléka and anti-balaka groups which led to thousands of deaths and left hundreds of thousands displaced. The investigation has led to three cases for five suspects, two of which are ongoing. On 16 December 2022, the Prosecutor announced the conclusion of the investigation, indicating “above all” that his Office is actively demonstrating “dynamic complementarity” in CAR, preparing to transfer relevant evidence to the Special Criminal Court (SCC), sharing expertise and best practices, particularly in witness protection, to bolster the Court’s capabilities. In October 2022, FIDH, the Observatoire centrafricain des droits de l’homme (OCDH) and the Ligue centrafricaine des droits de l’homme (LCDH) published a report critically analysing complementarity between national and international justice mechanisms and proposing a series of recommendations for a more complete, lasting, and effective justice system for victims and survivors in CAR. In October 2022, the SCC issued its first verdict, convicting three former members of the armed group known as “3R” of crimes against humanity and war crimes. The judgment became final in July 2023 after it was appealed before the Appeals Chamber of the SCC. While this is a step towards the fight against impunity in CAR and bringing justice closer to victims, continued efforts are needed to bring about meaningful complementarity.
5. Kenya (investigation concluded on 27 November 2023): In 2010, the OTP opened the inv
