Mainstreaming Investment Treaty Jurisprudence: The Contribution of Investment Treaty Tribunals to the Consolidation and Development of General International Law

The use of internal and external precedent has been studied in relation to numerous international courts and tribunals. The participation of investment treaty tribunals in judicial dialogues or judicial cross-fertilization, by contrast, has remained underexplored. The present article closes this gap and analyses both the use of internal and external precedent by investment tribunals and the way other courts and tribunals, both international and domestic, engage with investment treaty jurisprudence. We argue that investment tribunals, after having used internal and external precedent to consolidate international investment law as a uniform legal regime and embed it in the fabric of international law, have generated a body of investment treaty jurisprudence that other courts and tribunals are now starting to use as an authoritative source for the determination of rules of general international law. In contributing to the development of general international law, investment treaty tribunals are slowly but steadily moving mainstream, from the periphery of international dispute settlement towards its center.