The Legal Authority of Non-State Rules: Application in International Commercial Contracts

This thesis examines the legal authority of non-state rules in international commercial contracts and their application in state courts. Non-state rules can be divided in uncodified rules and codified rules. Uncodified non-state rules are general principles of law, practices, trade usages, and custom. They have a customary origin. Codified non-state rules are model laws, restatements of law, standard terms and conditions, and guidelines. They are created by international organisations and trade associations. Non-state rules have legal authority in the national and the international sphere. Their legal authority can be established by looking at different factors: promulgator, substance, support, and application. It is especially the last factor which plays a deciding role in measuring their legal authority. This thesis uses three main case studies: France, England, and the US to understand the legal authority of non-state rules. After having established what non-state rules are and how their legal authority can be measured this thesis concentrates on their application in courts. It asks three important questions: when can non-state rules be applied? When are they applied? And how are they applied? There are four scenarios in which non-state rules are applied in descending degrees of legal authority: first of all, they are applied as the applicable law to the contract, secondly they are applied as sources of domestic law, thirdly they are used to interpret the applicable law, and fourthly they are applied as contractual rules. Legislations have a preference for uncodified non-state rules such as trade usages and general principles. These are often sources of domestic law. To apply these uncodified non-state rules judiciary resorts to codified non-state rules to go from the general principle to the practical application. After studying the application of non-state rules in depth, this thesis concludes with a framework and classification that leads to understanding the legal authority of non-state rules.