When a tribunal interprets a treaty it does so not in a vacuum or as an isolated decider, but as an adjudicator embedded in a large and dynamic universe of public international law—as Bruno Simma forcefully articulated in his separate opinion in Oil Platforms. Yet in recent years there have been decisions of investor-state tribunals, fortunately not in the mainstream but still much commented on, that adopt a much narrower, hide-bound approach to fair and equitable treatment, the most egregiously awful arguably being Glamis Gold v. United States, where the tribunal froze the meaning of fair and equitable treatment as the content of the standard of diplomatic protection of aliens in the early 20th century. By tracing the reciprocal influences flowing back and forth between investment treaty law and other areas of public international law, Martins Paparinksis’s article provides a good antidote to the misguided thinking behind rulings like Glamis. This thinking is based upon a number of assumptions. One is that investment treaties simply import through fair and equitable treatment a self-contained regime of diplomatic protection, rather than the fair and equitable treatment norm adapting concepts from diplomatic protection to a new context of investor protection, which operates not through espousal but direct access to dispute settlement by investors. Second is the strong presumption against customary law having evolved through the thickening jurisprudence of international and regional courts and tribunals. Third is the very notion that the law of diplomatic protection, or the minimum standard of treatment, is a kind of self-contained regime unaffected by developments in other areas of international law, whether human rights or, for example, various transparency and administrative fairness-type provisions in multilateral and regional economic treaties. All of these dubious assumptions are in effect challenged by Martins’ rich and textured analysis of the fair and equitable treatment standard within the large complex universe of public international law. As Martins shows, although some treaties may explicitly restrict the kind of normative material available for interpretation, in general the ambit is defined broadly, if one takes together Article 31 of the VCLT and Article 38 of the ICJ Statute. Because fair and equitable treatment is a treaty-based obligation, the normative material relevant to defining the standard need not itself have the status of custom. In any case, it is well established that in the modern universe of international law there is a dynamic interplay between custom, conventional law, even soft law. This reality makes the Glamis Gold approach seem particularly sterile or arid.
Also worth further thought in the context of Martins’ article is an issue he raised in his exchange with Anthea Roberts in the recent EJIL:Talk! discussion of his book: I agree with Martins that one should not lightly have reference to municipal public law as a source for the content of fair and equitable treatment, certainly not as a ceiling. To ensure fair and equitable treatment of an investor it is not enough that a host state have laws on the books that appear to be consonant with public law in other states. Evaluating the standard set by municipal public law would involve assessing not only the standard implicit or explicit in formal statutes but the actual workings of the system, in other words, administrative practice. Also, even between countries such as the US and Canada there are quite significant differences with respect to how administrative discretion is controlled by judicial review and other vital mechanisms. The risk of going down the path that Roberts suggests is that the fair and equitable treatment standard could become the lowest common denominator of public law and administrative practice among a certain select group of states. Another risk is that a host state might be considered to have discharged its state responsibility by having a working system of public law with certain formal guarantees, even if the investor is egregiously mistreated in the process. The fair and equitable treatment standard must, as the word treatment implies, be applicable not only to the laws of the host state, but also to the specific behavior of the host state towards the investor in question. Just as with human rights law, investor protection ought to provide relief against exceptional abuses even within systems of law that are not formally deficient. As Martins shows in his article, public international law as it is evolving in diverse areas provides adequately fertile normative material for an evolving international standard of fair and equitable treatment.