The concept of precedent has not received much attention in international law scholarship to date. International courts and tribunals are usually not formally bound by previous decisions. Nevertheless, there is no denying that precedents play a significant role in the practice of international courts. Courts cite and rely on previous decisions in order to lend their arguments more force. Two recently published studies aim to shed more light on this tension in the use of precedents: while Marc Jacob analyses precedents in the case law of the European Court of Justice, Valériane König examines the precedential effect of decisions in international arbitration. Both books not only analyse the same concept in different contexts, they also have a common methodological point of departure. They rely to a certain extent on an empirical analysis. They construct a database of decisions and draw several quantitative and qualitative inferences from this database. They thus contribute to a laudable trend in international law scholarship towards a greater focus on empirical analyses, even though the extent and the informational value of the quantitative analysis are limited in both cases.
Valériane König points out in her study on the precedential effect of international arbitral awards why arbitral awards are, at least prima facie, rather unlikely candidates to function as precedents. The principal task of arbitral tribunals is dispute settlement between private parties, not the progressive development of law. Furthermore, the parties often have a significant interest in confidentiality so that a vast number of arbitral decisions are not published. Nevertheless, arbitral tribunals often decide matters in which the normative predetermination through written norms is rather low. For this reason, precedents may have an important informational value and strengthen the consistency of the case law.