In the contemporary era, systematically documenting armed conflicts and international crimes is recognized as a cornerstone of international criminal justice. This study examines the role of fundamental principles in documenting international crimes within the judicial practice of the International Criminal Court (ICC), focusing on the Ukraine case. It explores how the Office of the Prosecutor aligns its actions with legal frameworks and operational standards. According to the Rome Statute and the ICC’s Rules of Procedure and Evidence, documentation must uphold independence, impartiality, confidentiality, and witness protection—principles also reflected in the Prosecutor’s Guidelines, the Joint Investigation Team’s cooperation, institutional documentation manuals, and foundational investigative directives in Ukraine.

The research question is: to what extent does the ICC’s practice in the Ukraine case reflect and ensure the implementation of these core documentation principles? Using a descriptive-analytical approach, this study employed systematic note-taking and qualitative analysis of data from ICC documents and judicial practices. The findings reveal that documentation is not merely a technical task but a dynamic process crucial for strengthening international criminal justice and effectively prosecuting perpetrators. In the Ukraine case, the Court employed a multi-dimensional approach grounded in humanitarian law, unprecedented institutional cooperation, and digital technologies for evidence preservation. Despite challenges—including limited state cooperation, political pressures, field constraints, and balancing evidence collection with victim-centered principles—the Court has made significant progress in realizing these principles.