I’ve been following with intense interest the back and forth on the Corner about the responsibility of the president to “preserve, protect, and defend” the Constitution and what that means regarding acts he believes are unconstitutional. The Constitution, as we all know, is a many-faceted document that not only dictates substantive outcomes but also creates particular government processes. For the sake of brevity, let’s call this substantive constitutionalism and procedural constitutionalism.

If a legislator or president believes any proposed legislation is unconstitutional on its merits, the proper procedural response is to vote against it or veto it. This much is obvious (and I’m still disappointed that President Bush didn’t veto McCain-Feingold when he had obvious constitutional concerns with the bill).

But once a bill is enacted, a president should not make substantive constitutional decisions without considering appropriate constitutional processes. His primary constitutional role is to execute the laws, not adjudicate the laws, and his oath to “preserve, protect, and defend” the Constitution also means maintaining his proper role. In short, violating the Constitution procedurally to defend the Constitution substantively is obviously problematic.

At the same time, common sense dictates — and history teaches — that our process can produce constitutionally grotesque outcomes, including outcomes that cannot be readily addressed through the judicial process. In other words, there is a line that presidents must be able to draw.

Ironically enough, Attorney General Holder properly articulated the line when he said the “Department has a longstanding practice of defending the constitutionality of duly-enacted statutes if reasonable arguments can be made in their defense, a practice that accords the respect appropriately [I would say “constitutionally”] due to a coequal branch of government.” In other words, an administration may disagree with an act — or even believe that it is not constitutional — but deference to constitutional processes compels the attorney general to represent the people unless there is no reasonable constitutional defense for the people’s action.

The outrage of the administration’s DOMA decision comes not from articulating this principle but from its declaration that, essentially, there are no reasonable constitutional arguments in support of Section 3 of the Defense of Marriage Act. This is a truly astonishing assertion given the great weight of legal authority — some of which is outlined in the attorney general’s own letter. In fact, that political (rather than legal) calculation underlying this determination is given away by the administration’s continued enforcement in spite of its alleged conviction that the act has no reasonable constitutional support.

The politics are fairly obvious. The administration knows that others will take up DOMA’s defense (and do it more ably than the Department of Justice, which had been barely putting up a fight), wants to fire up the Left, but it doesn’t want to go all the way and take an action — refusing to enforce the law — that would inflame many voters.

— David French is senior counsel at the Alliance Defense Fund Center for Academic Freedom.