This book illuminated the role of de facto international prosecutors as an emerging phenomenon. To that end, this study had two objectives.

First, and foremost, the primary aim was to explain how and why de facto international prosecutors, particularly private non-State actors, attempt to extend the reach of international criminal law. To do that, it brought together three biographical case studies to investigate how and why de facto international prosecutors adopt the tasks and practices of the offices of international prosecutors, particularly when the local judiciary is unable or unwilling to hold senior leaders suspected of core crimes to account. In particular, the book examined how witnesses and victims of core crimes – both historically and more recently – have played an essential role in closing the accountability gap. The study shows that rather than isolated incidents, de facto international prosecutors are an emerging phenomenon and an essential feature of the UN-System and global legal order.