Interpreting the ECHR in the Light of “Other” International Instruments: Systemic Integration or Fragmentation of Rules on Treaty Interpretation?

Often accused of being a threat to the coherence of international law, the ECtHR was indeed a pioneering international tribunal in showing the relevance of Art. 31.3.c of the Vienna Convention on the Law of Treaties (VCLT) in broadening the normative context for interpreting treaties. In doing so, it anticipated the principle of “systemic integration” recently singled out by the ILC as a crucial tool against the fragmentation of international law. In the Demir and Baykara v. Turkey judgment, the ECtHR has systematized its previous jurisprudence, elaborating a methodology of interpretation of the Convention in light of other international instruments. However, in doing so, it has adopted a language describing its approach as partially deviating from the customary rules on treaty interpretation, as codified by the VCLT. This chapter argues that, upon a closer analysis, the interpretative method of the Court may be, and should be, reconciled with the traditional approach, whose flexibility accommodates the special interpretative needs of human rights treaties. In this context, “systemic integration”, i.e. an interpretative reference to a wide international normative environment, far from being constrained by the narrow terms of Art. 31.3.c VCLT, should be constructed as a general principle of interpretation rooted in a plurality of hermeneutic approaches (textual, contextual and teleological). It concludes that, as far as interpretation is concerned, the Court should treat international law more carefully, avoiding unnecessary separatist statements.