International Law in Revolutionary Upheavals: On the Tension between International Investment Law and International Humanitarian Law

In a decentralized system such as public international law with its many and increasingly specialized subfields, it is well known that the question of how to deal with the relationship and interplay of its distinct subfields is particularly vexed. Moreover, this question becomes more acute when these subfields simultaneously claim authority and arrive at quite different, even conflicting, results for the same facts. Revolutionary upheavals can culminate in civil wars such as those in the wake of the ‘Arab spring’. In the course of such conflicts a foreign investor’s production site may be destroyed. Under international investment law, if government forces are sufficiently responsible for such a destruction, this may lead to a breach of a bilateral investment treaty. However, in remarkable contrast to this, under international humanitarian law of non-international armed conflicts, if the destruction was justified under the principle of ‘military necessity’, then, this state action could be considered lawful. So, how then should the possible tension between international investment law and international humanitarian law with their different objectives and values be conceptualized and importantly be decided by investment arbitration tribunals? Are international humanitarian law and international investment law at all applicable in these case constellations? If a conflict between the norms of both regimes emerges here, should it be resolved by the principle of ‘lex specialis’? On the other hand, one might wonder whether a normative conflict between international humanitarian law and international investment law really arises at all. Are reservations concerning a ‘lex specialis’ approach justified, and should rather a more informative approach be taken in which international humanitarian law’s rules and concepts inform the interpretation of bilateral investment treaties’ norms, and vice versa? Shall therefore the ‘extended war clause’ contained in bilateral investment treaties—which offer compensation for investments demonstrably destroyed in cases in which the destruction was not required by the ‘necessity of the situation’—be interpreted in the light of humanitarian law’s principle of ‘military necessity’? Or, are there compelling arguments for an autonomous treaty interpretation on its own terms? In this context, it is striking that respondent states have, as far as can be seen, apparently not yet attempted to argumentatively use humanitarian law’s principle of ‘military necessity’ in an investment arbitration. In those situations and cases, however, the respondent states are anyway often accommodated by the fact that it is, frequently, challenging for the plaintiff investor to prove attributability and causality. Finally, this raises the question whether is it compatible with the principles of fair trial and procedural equality that in these specific constellations the burden of proof remains on the plaintiff investor?