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PhD defence

To Detain, or Not to Detain: A Functional Approach to Non-State Armed Groups’ Activities in Non-International Armed Conflicts

  • E. Heffes
Tuesday 26 April 2022
Academy Building
Rapenburg 73
2311 GJ Leiden


  • Dr. R.W. Heinsch
  • Prof.dr. C. Stahn



During armed conflict, non-State armed groups (NSAGs) deprive individuals of their liberty on a regular basis. Examples can be found in Colombia, Afghanistan, Libya, Syria, Mali and the Democratic Republic of the Congo (DRC), among many others. Yet, examining these activities goes beyond its mere acknowledgment. This thesis explores the legal regulation of NSAGs’ detention activities in non-international armed conflicts (NIACs).

It does so by concentrating on NSAGs’ practices in this field, presenting and testing the hypothesis that certain rules of international law oblige these actors not to arbitrarily deprive individuals of their liberty. Furthermore, it argues that NSAGs must have a legal basis in order to undertake these activities. In addition, and by relying on a “legal pluralistic” approach of international law, that basis is to be found in those “laws” and regulations established by the groups themselves. Other options are also possible, such as the adaption of the State’s domestic law or an agreement concluded with a third party. Indeed, these “laws” and regulations could allow NSAGs to potentially respect their obligations in the field of detention, including the principle of legality.

PhD dissertations

Approximately one week after the defence, PhD dissertations by Leiden PhD students are available digitally 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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