In current public international law, normative regimes generally develop as the result of states' common interests. Various institutions are involved in the interplay of multilateral processes and diplomatic practices, which largely contributes to the development of legal regimes. Among those institutions, dispute settlement bodies play the vital role of interpreting and applying the relevant treaty law, customs and agreements which are the outgrowth of previous negotiations. However, the less-studied opposite might also be true: in some cases, judicial recourse and dispute settlement decisions can be used to influence treaty negotiations. As this chapter demonstrates, states can use a variety of institutions in order to attempt to influence and/or influence the outcome of treaty negotiations. Indeed, the dispute settlement mechanisms, for example in the WTO, help states to influence the negotiation of WTO-based treaties in the same policy areas. Thus, the dispute settlement mechanism and the treaty negotiation function of the same institution can form part of an overall policy of states to advance their treaty negotiation strategies.

Multidisciplinary approaches can be used to monitor the way that states use, or restrain from using, case law arguments in their negotiations. If there is indeed a link between dispute settlement based litigation and ensuing or concurrent negotiations, we should be able to observe it in the dispute settlement cases themselves from facts, from declarations by parties, and from the opinions of the deciders.