Domestic Law Concepts in International Investment Law and Arbitration

This book examines the challenges faced by international investment law when it encounters legal concepts used in and derived from domestic law. It demonstrates how these domestic law concepts raise distinct interpretive challenges and proposes that arbitrators must be careful not to import foreign ideas or invent ‘universal’ meanings without proof.

Gabriel M. Lentner provides a clear, principled method for deciding when to follow a specific state’s law, when a treaty uses a broader shared concept, or when a mix of both is necessary. He bridges domestic and international law by setting out how domestic law concepts enter investment law. The book treats legal concepts as context-dependent inference structures in order to highlight the importance of not simply borrowing domestic meanings in isolation. Lentner critiques a homeward bias in arbitral reasoning, especially when tribunals invoke domestic concepts as general principles of law without meeting the demanding evidentiary threshold under the doctrine of sources of international law.

Scholars and academics of international investment, private international law, and legal theory will benefit from the clear, analytical framework put forward. This book is also an essential resource for investment arbitration practitioners, treaty drafters, and policymakers looking to better understand how domestic law concepts play out in international investment law.