Reconciling the Dual-Faceted Mandates of Quasi-Judicial Human Rights Bodies: The Working Group on Arbitrary Detention’s Prima Facie Approach to Evidence

Focusing on evidentiary approaches, this article examines the burdens and standards of proof applied at United Nations quasi-judicial international human rights bodies. These bodies have dual-faceted mandates, combining legal and human rights traditions and imperatives. However, they diverge in their approach to evidence. This article argues that the prima facie approach developed over the Working Group on Arbitrary Detention's 30 years of jurisprudence provides an appropriately flexible and conceptually coherent means of accommodating combined human rights and the judicial mandates. Nonetheless, this approach requires lexiconic and taxonomical tightening, and clarification of its standard of proof. Comparing the approaches taken by other quasi-judicial bodies, this article builds the impetus towards inter-institutional consistency. It reviews proposals such as wholesale reversal of the burden of proof onto Governments. It highlights the drawbacks of that unilateral type of burden and the risks that it would introduce further uncertainty for parties to proceedings, may cause onerous difficulties for claimants, and would potentially flood the human rights institutions with unsubstantiated claims.