文档介绍：CHICAGO
JOHN M. OLIN LAW & ECONOMICS WORKING PAPER NO. 63
(2D SERIES)
A Theory of Customary International Law
Jack L. Goldsmith and Eric A. Posner
THE LAW SCHOOL
THE UNIVERSITY OF CHICAGO
This paper can be downloaded without charge at:
The Chicago Working Paper Series Index:
The Social Science work Electronic Paper Collection:
http://papers./?abstract_id=145972
A Theory of Customary International Law
Jack L. Goldsmith* and Eric A. Posner**
Customary international law (“CIL”) is one of two primary
forms of international law, the other being the treaty. CIL is
typically defined as a “customary practice of states followed from a
sense of legal obligation.”1 Conventional wisdom views CIL as a
unitary phenomenon that pervades international law and
international relations. Governments take care ply with CIL,
and often incorporate its norms into domestic statutes. National
courts apply CIL as a rule of decision, or a defense, or a canon of
statutory construction. Nations argue about whether certain acts
violate CIL. Violations of CIL are grounds for war or an
international claim. mentators view CIL to be at the core
of the study of international law.
And yet CIL remains an It lacks a centralized
lawmaker, a centralized executive enforcer, and a centralized,
authoritative decision-maker. The content of CIL seems to track the
interests of powerful nations. The origin of CIL rules is not
understood. We do not know why ply with CIL, or even
what it means for a nation ply with CIL. And we lack an
explanation for the many changes in CIL rules over time. Both parts
* Associate Professor of Law, University of Chicago.
** Professor of Law, University of Chicago. Thanks to Jaqueline Bhabha, Richard
Epstein, Tracey Meares, Richard Ross, Cass Sunstein, Doug Sylvester, Adrian
Vermeule, and participants at a workshop at the University of Chicago Law
School ments, and to Christopher