Government 1740

1. Government 1740 INTERNATIONAL LAW Summer 2008 Lecture 4: Sources of International Law: Custom and Treaties

2. OUTLINE I. Sources of International Law II. Customary International Law (CIL) A. What it is B. Theories critical of CIL II. The Nature of Treaty Obligations A. Definition B. Pacta Sunt Servanda C. The Vienna Convention D. Invalid Treaties III. How Treaties are Made: From Negotiation to Interpretation IV. Treaty Termination: cooperatively, unilaterally, and exceptional circumstances

3. I. Sources of International Law • Article 38 of the International Court of Justice: • Treaties • Custom • General Principles of Law • Judicial Decisions • Writings of Jurists

4. Customary International LawThe “Traditional View” • Rules that evolve from state practice • What constitutes custom? • Broad acceptance, regularity, duration of a practice • Opinio juris • Why is custom binding? • The contestation of custom – critics?

5. Theories Critical of Customary International Law • Normative critique: weakly linked with consent. • Positive critique: • CIL does not explain foreign policies or world politics. • It only reflects the interests and practices of the most powerful environment interests behavior

6. Other sources of International Law • General Principles of law • Judicial Decisions • Writings of Jurists

7. II. The Nature of Treaty Obligations Treaty: An international agreement between two or more subjects of international law which is intended to create rights and obligations for the parties to it

8. Basic Principles of Treaty Law Pacta Sunt Servanda: Agreements must be served; they are binding 1969 Vienna Convention on the Law of Treaties

9. Unauthorized negotiator Essential error of fact Impose obligations on third parties Invalid Treaties

10. Invalid Treaties • Against prevailing norms or illegal

11. Invalid Treaties? • Concluded under the threat or use of force (VCLT Article 52) Treaty of Nanking Opium Wars

12. Invalid Treaties? Treaty of Versailles • Concluded under the threat or use of force

13. Invalid Treaties? • Concluded under the threat or use of force Guantanamo Bay

14. III. How Treaties are Made • Negotiation • All treaties begin with politics • Shaped by power, interests, bargaining, and persuasion.

15. Treatymaking, continued... • Adoption: agreement on a final text Signature: signing of adopted text Ratification: done by the executive of each country, according to domestic rules that typically involve the legislature

16. “...the exclusion or modification of the legal effect of certain treaty provisions.” Reservations:

17. ICCPR Reservations: United States: • "(2) That the United States reserves the right, subject to its Constitutional constraints, to impose capital punishment on any person (other than a pregnant woman) duly convicted under existing or future laws permitting the imposition of capital punishment, including such punishment for crimes committed by persons below eighteen years of age.”

18. Other Aspects of Treaty-making • Accession/Adhesion • Entry Into Force • Interpretation

19. IV. Treaty Termination • Terms of the Treaty itself • Notice • Explicit or Tacit Agreement • Violation by one side • Clausula rebus sic stantibus • State Extinction

20. Summary: • Treaties are the most important source of international law, followed by custom • Custom requires a pattern of behavior, as well as a widespread belief that a norm is obligatory (opinio juris) • Pacta sunt Servanda: Treaties are to be observed • Secondary rules have developed on Treaty Law: Vienna Convention 1969 • Through Treaty Law, states are trying to achieve a balance between: • Certainty and Flexibility • Obligation and Consent