Means of Interaction between EU and International Law: Customary International Law as a Source of EU Law: A Two-Way Fertilization Route?

Summary:

The object of this article is to shed light on the extent to which custom constitutes a source of EU law, which binds the EU institutions in their executive, legislative, and judicial capacity. It is argued that custom can be a source of EU law to the extent that the EU Treaties do not address a particular issue. Custom (if applicable) may also be invoked before the CJEU to regulate a specific point.

The article commences with a discussion of custom as a gap-filler. Then it will be examined whether Member States and individuals can rely on custom in order to challenge EU law. Since custom may be geographically ‘universal’ (global) or ‘regional’ in scope, the article concludes by discussing whether EU law can generate custom—hence establishing, as the title suggests, a two-way fertilization route.

Further information:

This article is part of the Special Issue: EU Law and Public International Law: Co-implication, Embeddedness and Interdependency.

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