A Horizontal Treaty on Cooperation in International Criminal Matters: The Next Step for the Evolution of a Comprehensive International Criminal Justice System?

This paper addresses the intersection between two key concepts in international criminal justice, namely cooperation and complementarity. While it is recognised that domestic courts carry main responsibility for ensuring accountability for the commission of international crimes, there appears to be gaps in two areas. First, international law does not make provision for a comprehensive obligation to investigate and prosecute such crimes. Second, there is no comprehensive and robust interstate cooperation obligation, necessary to ensure successful domestic investigations and prosecutions. The paper assess two initiatives designed to fill these gaps, and considers their strengths, weaknesses and the possible synergies between them