Because of the novelty and complexity of the issues, any judgments on the constitutional issues must be at least a bit tentative.

To summarize my view: S. 1740 is unprecedented in our nation’s history; it is probably either pointless or unconstitutional; and while the constitutional issues are far from simple, it is safe to say that S. 1740 is a constitutionally ill-advised intrusion into a problem handled at the state level.

S. 1740 responds to an old problem, not a new one, and that problem — diverse state laws about marriage has been settled for a long time without national intervention. Thus there is a reasonable view that S. 1740 is pointless; it adds nothing to current law. If S. 1740 is not pointless — if states must give full faith and credit to the relevant marriages — S. 1740 may well be unconstitutional. In the nation’s history, Congress has never declared that marriages in one state may not be recognized in another; it has not done this for polygamous marriages, marriages among minors, incestuous marriages, or bigamous marriages. It is unclear if Congress has the authority to enact such a bill under the commerce clause, the full faith and credit clause, or any other source of national authority. In addition, S. 1740 raises serious issues under the equal protection component of the due process clause in the aftermath of the Supreme Court’s recent decision in Romer v. Evans.

This scenario is, however, unlikely, for the full faith and credit clause has never been understood to bind the states in this way. For over two hundred years, states have worked out issues of this kind on their own. It is entirely to be expected that in a union of fifty diverse states, different states will have different rules governing marriage. American law has carefully worked out practical strategies for ensuring sensible results in these circumstances, as each state consults its own “public policy,” and its own connection to the people involved, in deciding what to do with a marriage entered into elsewhere. In short: States have not been bound to recognize marriages if (a) they have a significant relation with the relevant people and (b) the marriage at issue violates a strongly held local policy.

Thus, for example, the first Restatement of Conflicts says that a marriage is usually valid everywhere if it was valid in the state in which the marriage occurred. But section 132 lists a number of exceptions, in which the law of “the domicile of either party” will govern: polygamous marriages, incestuous marriage, marriage of persons of different races, and marriage of a domiciliary which a state at the domicile makes void even though celebrated in another state.

The Second Restatement of Conflicts, via section 283, taken a somewhat different approach. It says that the validity of a marriage will be determined by the state that “has the most significant relationship to the spouses and the marriage.” It also provides that a marriage is valid everywhere if valid where contracted unless it violates the “strong public policy” of another state which had the most significant relationship to the spouses and the marriage at the time of the marriage. Thus a state might refuse to recognize incestuous marriages, polygamous marriages, or marriage of minors below a certain age.

The two Restatements show that it is a longstanding practice for interested states to deny validity to marriages that violate their own public policy. Many cases have reflected a general view of this kind. See, e.g., In re Vetas’s Estate, 170 P.2d 183 (1946); Maurer v. Maurer, 60 A.2d 440 (1948); Bucea v. State, 43 N.J. Super 815 (1957); In re Takahashi’s Estate, 113 Mont. 490 (1942); In re Duncan’s Death, 83 Idaho 254 (1961); In re Mortenson’s Estate, 83 Ariz. 87 (1957). There is no Supreme Court ruling to the effect that this view violates the full faith and credit clause.

All this suggests that S. 1740 would respond to an old and familiar problem that has heretofore been settled through long-settled principles at the state level and without federal intervention. If some states do recognize same-sex marriage, the problem would be handled in the same way that countless similar problems have been handled, via “public policy” judgments by states having significant relationships with the parties. Different “public policies” will produce different results. This is consistent with longstanding practices and with the essential constitutional logic of the federal system. The greater irony is that the Hawaii legislature has recently made clear that a marriage is available only between a man and a woman, and hence there is no current problem that S. 1740 would address. I conclude that S. 1740 is constitutionally ill-advised because it intrudes, without current cause, into a traditional domain of the states.

If this traditional view is correct, S. 1740 is also pointless; it gives states no authority that they lack. But a lurking question remains: Why, exactly, does the full faith and credit clause not require states to recognize marriages celebrated elsewhere? The Supreme Court has not offered an explanation. Perhaps the answer lies in the fact that a marriage is in the nature of a contract, and hence it is not a “public Act, Record, [or] judicial Proceeding” within the meaning of the Clause. Perhaps the answer lies in the longstanding view that a state with a clear connection with the parties and strong local policies need not defer to another state’s law. In either case there is no reason to enact S. 1740. But if the full faith and credit clause is interpreted to require states to respect certain marriages, and if S. 1740 negates that requirement, S. 1740 raises serious constitutional doubts.

(a) Full faith and credit

The purpose of the full faith and credit clause was unifying — the clause was designed to help create a “United States” in which states would not compete against one another through a system in which judgments could be made part of interstate rivalry. The clause’s historic function is to ensure that states will treat one another as equals rather than as competitors. In this way, the full faith and credit clause is akin to the commerce clause, operating against protectionism, in which one state uses its power over its persons and territories to punish outsiders. See Jackson, Full Faith and Credit — The Lawyer’s Clause of the Constitution, 45 Column L. Rev. 1 (1945).

For reasons just stated, the full faith and credit clause has not been understood to mean that each state must recognize marriages celebrated in other states. But does the full faith and credit clause authorize S. 1740 if it is understood to give states permission to ignore judgments by which they would otherwise be bound? This is not clear. An affirmative answer might be supported by the following language: “And the Congress may by general Laws prescribe the Manner in which such Acts, Records and Proceedings shall be proved, and the effect thereof.” Perhaps Congress can say that some Acts, Records and Proceedings are of “no effect.” Perhaps Congress’ power over “the effect thereof” means that Congress can decide which Acts, Records and Proceedings have “effect.” The question, then, is whether Congress may not only prescribe the manner of proof and also implement the clause by requiring “effect” upon certain proofs (what we might call the accepted “affirmative” power), but also say that certain Acts, Records, and Proceedings may be without effect when, in the absence of legislation, they would have effect (what we might call the “negative” power). Does the negative power exist, and how might it be limited? (Even if it does, Congress would have no power here if a marriage is not an Act, Record, or judicial Proceeding. I put that point to one side.)

This is a complex and difficult question, and no Supreme Court decision gives a clear ruling. A detailed historical study of the grant of power to Congress seems to suggest that the grant was designed to ensure that Congress could implement the full faith and credit clause by expanding the reach of state rules and judgments. That is because the clause has above all a unifying power. See Cook, The Powers of Congress Under the Full Faith and Credit Clause, 28 Yale LJ 421 (1919). In this view, the clause may well authorize Congress (for example) to make state judgments directly enforceable in other states, compel states to recognize rights created.