Skip to Main Content

Treaty Research Guide: Rule 21.4 of Bluebook

Focus: Bluebook-compliant treaty sources.

Treaty Finding Aids

TIP: This guide's top-level tab: Rule 21.4 of Bluebook provides a pull-down menu of links to preferred treaty sources highlighted in The Bluebook's treaty rule.

Frequently Used Finding Aids:

Tips To Apply Rule 21.4 (Treaties) of The Bluebook

1. If you do not know what the abbreviations in rule 21.4: Treaties stand for, Table 4 of The Bluebook: A Uniform System of Citation (Columbia Law Review Ass'n et al. eds., 21st ed. 2020) provides full titles of abbreviated treaty sources. 

2. To apply rule 21.4, determine whether the U.S. is a party to the treaty.

Sources that answer this threshold question:

  • United Nations Treaty Collection, MTDSG, tab: Status of Treaties
  • U.S. Department of State, Treaties in Force (+ 2021-2023 supplement)
    • Provides cites to treaties currently in force to which the U.S. is a party.  You will see cites to previously published United States Treaties and Other International Agreements series (U.S.T.) and to currently published Treaties and Other International Acts Series (T.I.A.S.).
    • If Treaties in Force index does not reference a recent U.S. treaty, try consulting these U.S. Department of State Office of Treaty Affairs web pages: Recent Actions for Treaties for Which the United States is Depositary and Treaties Pending in the Senate.  
  • Institute of Advanced Legal Studies, University of London (host), Flare Index to Treaties 
    • Provides cites to 2,000+ multilateral treaties (scope: "key multilateral treaties from the 1600s onwards" + "key bilateral treaties from 1353 to 1815"). 
    • Cites include Bluebook-preferred sources.   
  • Westlaw > Secondary Sources > Law Reviews & Journals
    • Search by a treaty's title or popular name and note how scholarly legal journals have cited to the treaty.  

3. If you find a cite to the treaty, copy the cite.

4. If the U.S. is a party to the treaty, apply either rule 21.4.5(a)(i) [primarily: bilateral treaties] or rule 21.4.5(a)(ii) [multilateral treaties].

5. If the U.S. is not a party to the treaty, apply rule 21.4.5(b).

  • Requires researchers to cite to one source published by an international organization.
  • If a treaty does not appear in a source published by an international organization, researchers can cite to the treaty in the unofficial document collection: International Legal Materials (I.L.M.). Finally, if a treaty does not appear in International Legal Materials, researchers can cite to the treaty as posted at a government's website, an intergovernmental body's website, or other sources listed in rule 21.4.5(c) of The Bluebook.

Components of a Bluebook-compliant Cite

Components of a Bluebook-compliant treaty cite:

  • Treaty name
  • Abbreviated names of treaty parties (include only if treaty is between 2 parties)
  • Reference to a specific treaty article (example: art. 1) or subdivision, if you wish to create a pinpont cite
  • Date of signing (or, if parties signed treaty on different dates: date opened for signature, approved, ratified or adopted & indicate significance of date in italics)
  • Treaty source or sources


Bilateral treaty & U.S. is a party:

Convention for the Avoidance of Double Taxation and the Prevention of Fiscal Evasion with Respect to Taxes on Income, U.S.-Austl., art. 1, Aug. 6, 1982, 35 U.S.T. 1999. 

Multilateral treaty & U.S. is a party:

Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, Including the Moon and Other Celestial Bodies art. 6, adopted Dec. 5, 1979, 18 U.S.T. 2410, 610 U.N.T.S. 205.

Multilateral treaty & U.S. is not a party:   

Vienna Convention on the Law of Treaties art. 32, opened for signature May 23, 1969, 1155 U.N.T.S. 331.


When Was This Guide Last Updated?

This LibGuide was last substantively updated:

On: May 2, 2024

At:  11:23 AM

By: Jean Davis