One of the most nettlesome objections to extending congressional representation to the residents of Washington, D.C., is that it requires a constitutional amendment. Many Republicans say this, which is hardly surprising. But it’s also the position of Sen. Joe Manchin III (D-W.Va.), whose opposition could doom the effort.

Now, however, several dozen leading constitutional law experts are weighing in with a new letter that seeks to demolish this argument once and for all, making the case that granting D.C. statehood is absolutely within Congress’ constitutional authority. This should give the cause a big boost at a critical moment.

“Congress should not avoid exercising its express constitutional authority to admit the Commonwealth into the Union,” states the letter, which is signed by Harvard’s Laurence Tribe and Georgetown’s Caroline Fredrickson, among many others.

The dispute captures a raw, ugly truth about this moment: The window to correct serious structural flaws and imbalances in our system is very small. This requires Democrats to find the spine to make arguments outside their comfort zone, and act on them. If not, that window could slam shut.

The House passed legislation to make Washington, D.C., the 51st state and to grant its more than 700,000 residents full representation in Congress. (Amber Ferguson/The Washington Post)

The argument that D.C. statehood is unconstitutional begins with the fact that D.C. is the seat of the federal government. Thus, D.C. supposedly must remain under federal jurisdiction and Congress cannot make it a state.

The Constitution directs that “New States may be admitted by the Congress into this Union.” As the experts’ letter puts it: “Every state admitted into the Union since the Constitution was adopted has been admitted by congressional action.”

That objection is dealt with in the D.C. statehood bill that the House passed in April, the D.C. Admission Act, which is before the Senate. It defines the nation’s capital to include the White House, the Capitol, the Supreme Court and other federal buildings, leaving these under federal sovereignty, while making the rest of D.C. a state.

In this sense, the bill would not technically make D.C. a state. It would make the non-federal part into a new state, called Washington, Douglass Commonwealth, named after abolitionist Frederick Douglass. This is what’s meant by the shorthand “D.C. statehood.”

But opponents make another objection: They say the 23rd Amendment precludes D.C. statehood. That 1961 amendment deals with D.C.’s non-state status by empowering Congress to grant D.C.’s residents the number of presidential electors that it would enjoy if it were a state, though not more than the least populous state does. Congress passed a law enforcing that amendment.

Because of this, opponents claim, D.C. statehood would improperly leave the small area housing the federal government with presidential electors, while also granting electors to the new state.

Thus, opponents say, Congress can’t grant D.C. statehood without repealing the 23rd Amendment, which requires another amendment. Manchin has endorsed this view.

One of the key goals of the constitutional law experts’ letter is to challenge this argument.

First, the letter notes that the new D.C. statehood bill already deals with the problem. It repeals the congressional action that awarded D.C. those electors under the 23rd Amendment. As the letter argues, the 23rd Amendment did not require Congress to pass the law awarding those electors in the manner it did; it simply empowered Congress to do so.

Congress can thus repeal it. If it did, the seat of government would no longer get any electors. The rest of D.C. would become a state, and its 700,000 residents would get electors and congressional representation.

Second, the letter notes that Congress has another way to handle the problem. As the letter argues, Congress could simply require that the electors for the seat of government (which would not be a state) must go to the winner of the electoral college vote, rendering those electors meaningless.

The bottom line is that the 23rd Amendment isn’t an obstacle to Congress’ constitutional authority to create this 51st state:

The contention that a constitutional amendment is required to admit the Commonwealth is incorrect. The D.C. Admission Act calls for a proper exercise of Congress’ express authority under the Constitution to admit new states, a power that it has exercised 37 other times since the Constitution was adopted.

The letter argues that the courts likely won’t even hear a legal challenge to this, since it’s a “paradigmatic political question.” It shrewdly quotes an old opinion along these lines from Viet Dinh, a lawyer under President George W. Bush who is now the Fox Corp.’s chief legal officer and a major power player there, so it’ll be interesting to see how Fox covers this.

Opponents make many other arguments against D.C. statehood, which Paul Waldman has debunked at length. Among the silliest is the idea that doing this will benefit Democrats by adding two new senators.

That may be, but as Heather Cox Richardson notes, states have often been added for many reasons, including partisan benefit to the party adding them. And this in no way diminishes the idea that this is the right thing to do because D.C. residents are entitled to representation.

“The normative reason for it is democracy,” the University of Michigan Law School’s Leah Litman, one of the signatories, told me. Litman added that Congress is empowered to add states “to afford representation to United States citizens,” extending to them the blessings of “self-government.”

Indeed, that objection itself confirms the real reason Republicans are opposed. It would add representation for a large number of Americans who overwhelmingly vote Democratic (and also happen to be urban and majority-minority).

Whether it’s D.C. statehood, or reforming the filibuster crippling legislative action to address big public problems, or safeguarding voting rights against escalating restrictions on them, Democrats have a tight window for undertaking major rebalancing reforms. And act they must.

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