This article provides a comprehensive overview of the use of World Trade Organization (WTO) rules and case law by other dispute settlement mechanisms (DSMs) in international law. Our findings show that DSMs frequently refer to WTO rules and case law not only on matters of procedure but also on various substantive aspects of trade law and general international law. The 150 identified references vary in their quality and importance for the rationale of the DSM. They range from a footnote en passant to being at the core of the solution for a particular legal problem that the adjudicator or arbitrator faces. We cluster our findings into four major categories of circumstances under which other DSMs deem it appropriate to cite the WTO (factual determinations, procedural aspects, general principles of international law or the rules on treaty interpretation, and substantive rules).A more difficult task has been to draw tentative conclusions as to the reasons that motivate DSMs to look specifically into WTO rules and case law. In most instances, this is due to the fact that the terms or their context in a given applicable law of a regional trade mechanism resemble those of the WTO disciplines. However, the use of the WTO precedent for purposes of procedure and clarification of general principles of international law or the rules on treaty interpretation show a broader influence of the WTO on international dispute settlement.
Journal of World Trade