I have written this piece for Slate. It begins:

The Supreme Court’s unsigned majority opinion in Trump v. Anderson, ending Colorado’s attempt to disqualify Donald Trump from appearing on the ballot as an insurrectionist, is a remarkable self-own. It simultaneously turned what could have been a short, sweet (if weakly reasoned) unanimous holding about states not having the individual power to disqualify presidential candidates from their ballots into a bitter 5–4 dispute over the scope of Congress’ power to disqualify candidates. And if the majority felt that it needed to take the heat from the court’s liberals and from Justice Amy Coney Barrett because it wanted to provide clarity that Congress cannot try to disqualify Trump if he appears to be reelected when Congress counts Electoral College votes on Jan. 6, 2025, it made a mess. Leading scholars and lawyers reading the opinion already disagree over what Congress can do and how, keeping the door open to potential chaos. It’s a rare miss by a usually strategic and savvy Chief Justice John Roberts….

The Supreme Court’s unsigned majority opinion in Trump v. Anderson, ending Colorado’s attempt to disqualify Donald Trump from appearing on the ballot as an insurrectionist, is a remarkable self-own. It simultaneously turned what could have been a short, sweet (if weakly reasoned) unanimous holding about states not having the individual power to disqualify presidential candidates from their ballots into a bitter 5–4 dispute over the scope of Congress’ power to disqualify candidates. And if the majority felt that it needed to take the heat from the court’s liberals and from Justice Amy Coney Barrett because it wanted to provide clarity that Congress cannot try to disqualify Trump if he appears to be reelected when Congress counts Electoral College votes on Jan. 6, 2025, it made a mess. Leading scholars and lawyers reading the opinion already disagree over what Congress can do and how, keeping the door open to potential chaos. It’s a rare miss by a usually strategic and savvy Chief Justice John Roberts.

The legal question at issue is as arcane as it is central to democracy. After the Civil War, Congress passed three amendments to the Constitution, among them the 14^th Amendment. That amendment most notably protects individuals when states deprive people of their rights to due process or equal protection. But it also includes a provision, in Section 3, aimed at those who were part of the Confederacy during the war, disqualifying from future office those who had formerly pledged to uphold the Constitution but who later engaged in insurrection.

Relying on this part of the 14^th Amendment, some Trump opponents have gone state by state, arguing that Trump cannot appear on the ballot because he’s disqualified for his conduct in trying to overturn the results of the 2020 election. They lost in most places, but they won in Colorado and got Trump kicked off the ballot in that state. The U.S. Supreme Court stepped in, and in a short opinion issued on Monday (a per curiam, with no one justice listed as author), it held that states cannot enforce Section 3 when it comes to federal offices. Among other things, the court held that this would create “chaos” through a “patchwork” of state approaches to whom and how to disqualify. (Never mind that states already have a patchwork of rules, for example dealing with how third-party candidates can get on the ballot.)

Despite the unanimity on this point, the court included a five-paragraph Part II.A of the opinion, a section that generated tremendous controversy and to which Barrett and the three liberal justices objected. In those paragraphs—backed by Roberts, as well as Justices Samuel Alito, Brett Kavanaugh, Neil Gorsuch, and Clarence Thomas—the court explained that Section 3 empowers Congress, and apparently not other actors, to “prescribe” how disqualification is to work, at least as to federal officers. When Congress wishes to disqualify, it must aim at “particular individuals.” When Congress makes these determinations, “proceedings, evidence, decisions, and enforcement of decisions, more or less formal, are indispensable,” the majority wrote, quoting an 1869 opinion for a Supreme Court justice sitting as a circuit justice (and not an opinion of the Supreme Court).

Although the majority called Congress’ power “critical” when it comes to Section 3, without explaining what that means, it made the Supreme Court the final arbiter of whether someone can be disqualified. Congressional determinations of disqualification are “subject of course to judicial review to pass ‘appropriate legislation’ to ‘enforce’ the Fourteenth Amendment.” And later, in a part of the opinion joined by Barrett but objected to by the liberals, the court reiterated that any legislation passed by Congress to enforce Section 3 must be “tailored.” Legislation must reflect “congruence and proportionality” between means and ends, code words the court has used elsewhere to strike down congressional legislation.

The majority did not explain how far its holding goes. Is congressional legislation always required to enforce Section 3? There’s not a mention of the elephant in the room, which is what happens on Jan. 6, 2025, when Congress counts electoral votes. Can Democrats opt to not count votes for Trump on the grounds that he’s an insurrectionist? Would that require a prior statute? Or is the power to disqualify when counting Electoral College votes something within Congress’ powers under the 12^th Amendment, separate from the rules on statutes? If it’s under the 12^th Amendment, is it not subject to judicial review? Could Congress by statute otherwise disqualify Trump after the election?

The court did not answer these questions, and experts and members of Congress are already divided on them. It’s not even clear whether statutes already on the books are currently enforceable—including 18 U.S.C. §2383, which criminalizes insurrections and includes as a penalty prohibition from federal office—with different analysts reaching different conclusions. In terms of clues on the timing question, the five-justice majority did include this less-than-definitive section near the end:

An evolving electoral map could dramatically change the behavior of voters, parties, and States across the country, in different ways and at different times. The disruption would be all the more acute—and could nullify the votes of millions and change the election result—if Section 3 enforcement were attempted after the Nation has voted. Nothing in the Constitution requires that we endure such chaos—arriving at any time or different times, up to and perhaps beyond the Inauguration.

Would Congress disqualifying Trump under its 12^th Amendment powers to count Electoral College votes be “Section 3 enforcement … attempted after the Nation has voted”? Is that forbidden?…