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PhD defence

The Rome Statute as Evidence of Customary International Law

Tuesday 9 April 2019
Academy Building
Rapenburg 73
2311 GJ Leiden


  • Prof. W.A. Schabas


PhD defences are free; you do not have to register.


This dissertation provides a detailed analysis of the practical and urgent issue concerning the 1998 Rome Statute of the International Criminal Court as evidence of customary international law. The dissertation is composed of seven chapters, including the introduction and conclusions. Chapter 2 sets out a flexible formula of the two-element identification approach, focusing more on opinio juris, and clarifies the term ‘declaratory’ that defines the relationship between treaty and custom. Based on the methodology and the terms illustrated in chapter 2, chapters 3-6 address key issues of war crimes, crimes against humanity, indirect co-perpetration and personal immunity.

This dissertation concludes that provisions of the Rome Statute were partly declaratory of custom when adopted in 1998, and that they are also partly declaratory of custom at the present time. This dissertation will hopefully provide a perspective to understand part of the corpus of customary law applicable in the field of international criminal law which could be of value to legal practitioners of States.

Extended summary (pdf)

PhD dissertations

PhD dissertations by Leiden PhD students are available digitally after the defence through the Leiden Repository, that offers free access to these PhD dissertations. Please note that in some cases a dissertation may be under embargo temporarily and access to its full-text version will only be granted later.

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+31 71 527 3282

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