The "Defense of Marriage Act" (DOMA) Section 3 has been struck down. That may not be news to you by now.  If you ask me, striking it down was the easy part. Much harder is defending the Act on the grounds that the Supreme Court should show deference to the wisdom of Congress, in the same week that you vote to strike down the core of the Voting Rights Act; the dictionary entry for "chutzpah" just got a new entry. (For more on this, see Lawrence Tribe's analysis.)

Somewhere in between, on the hardness scale, is figuring out how to cite DOMA section 3 now.  Wikipedia admirably shows the full, correct legal citation [for DOMA], with links:  Pub.L. 104–199, 110 Stat. 2419, enacted September 21, 1996, 1 U.S.C. § 7and 28 U.S.C. § 1738C . This shows how many ways there were to cite the law tricky the legal citation problem was before today's Court opinion. But now that section has been invalidated by the Supreme Court. That doesn't take it out of the U.S. Code or affect its legislative history. So where to put the information that it is no longer valid under U.S. law? Lawyers will use the time worn tradition of parentheticals, like: 1 U.S.C.  7 (nixed by the Supreme Court) or 28 U.S.C. 1738C (squashed like a bug, c.f. United States v. Windsor).

But these parentheticals are not standardized, and are not logically part of the citation unit.  More concretely, in assigning a UUID to DOMA section 3, how should the court's opinion be incorporated? Assuming an XML model, is this a separate attribute on the reference element (e.g. validity="invalid")? Should there be a flag in the id itself? (e.g. href="DF3Ae8362-invalid") And should invalidation by the Court be distinguished, in the data, from repeal of the section by Congress? As was pointed out to me, this information may be added, in the future, as a Constitutionality note such as 19 U.S.C. 535 note.

Your thoughts are welcome. I plan to incorporate them, and excellent feedback (by Tim Arnold-Moore, +Robert Richards, +Sean McGrath and others) that I've gotten on my previous post on UUID's into an follow-up post on UUIDs for legal texts.

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A note on the legislative history of DOMA section 3, that points to the more general need for a *unique* identifier for legal documents: For starters, DOMA was 104 H.R. 3396 (pdf), and passed as Public Law 104-99 in 1996. It Section 2 amended "Chapter 115 of title 28, United States Code ... by adding after section 1738B" a new section, 28 U.S.C. 1738C,. That section, itself, includes the specific instruction to amend while Section 3 amends Chapter 1 of Title 1 of the U.S. Code (which itself was passed as the Dictionary Act) by adding a new section 7.
Note: Following comments I received from a U.S. Code expert, this post has been corrected to reflect the correct structure of the Act and its effect on the U.S. Code.