As House Democrats move forward with a resolution urging the removal of President Trump under the 25th Amendment as well as an effort to impeach him a second time, some lawmakers are looking at a third potential response to last week’s assault on the U.S. Capitol in Washington: invoking Section 3 of the 14th Amendment, which disqualifies federal and state officeholders who “have engaged in insurrection or rebellion” from holding office again.

A number of commentators have suggested that Section 3 of the 14th Amendment would allow the House and Senate to bar Trump from future office by a simple majority vote. This possibility gained additional attention after House Speaker Nancy Pelosi (D-Calif.) asked members of her caucus in a letter Sunday to share their views about that provision of the 14th Amendment. But lawmakers shouldn’t be misled by claims that the 14th Amendment option would be quick and easy. It is true that Congress potentially can use the amendment to bar Trump from future office, but the process will very likely take several steps and years.

Ratified in 1868, three years after the end of the Civil War, the 14th Amendment is best known for its twin guarantees of equal protection and “due process of law.” Less well known (until last week) is the amendment’s third section, which was enacted to exclude former Confederates from holding federal and state office. Section 3 of the 14th Amendment applies specifically to people who have sworn an oath to support the federal Constitution and then take part in insurrection or rebellion against the United States or give “aid or comfort” to America’s enemies. The penalty for disloyalty is disqualification from again holding federal or state office (unless two-thirds of the House and Senate vote to lift the ban).

But how, exactly, can Congress invoke Section 3’s penalties? The provision itself doesn’t say. Another part of the 14th Amendment — Section 5 — empowers Congress to enforce the entire amendment “by appropriate legislation.” Some have interpreted Sections 3 and 5 in tandem to suggest that a majority of the House and Senate — with the president’s signature — could enact a law applying Section 3’s lifetime ban to particular individuals.

There’s a problem with this theory, though. A provision in the original 1787 Constitution — Article I, Section 9, Clause 3 — prohibits Congress from passing any “bill of attainder.” A bill of attainder is a law declaring a specific person to be guilty of a crime and prescribing a punishment. The bill of attainder clause reflects the principle that the judiciary, not the legislature, is responsible for adjudicating guilt and meting out justice.

It might be argued that the 14th Amendment, which came eight decades after the original Constitution, carved out an implicit exception from the bill of attainder ban for insurrectionists and rebels. But Chief Justice Salmon Chase rejected that argument in an 1869 case involving a challenge to a sentence handed down by an ex-Confederate judge. “[I]t is a necessary presumption,” Chase wrote, that amendments “seek to confirm and improve, rather than to weaken and impair the general spirit of the constitution.” Chase suggested that Congress could establish mechanisms to ascertain whether particular individuals had participated in insurrection or rebellion, but that these mechanisms should respect the Constitution’s existing procedural guarantees against targeted legislative punishment.

One year after Chase’s opinion, Congress passed the First Ku Klux Klan Act, which established procedures for enforcing Section 3. Whenever a former Confederate occupied federal or state office in violation in Section 3, the Ku Klux Klan Act called on federal prosecutors to bring an action in federal court to remove the officeholder. The statute also made it a misdemeanor for any person to knowingly accept, hold, or attempt to hold any office for which he is ineligible under Section 3. The upshot was that courts — not Congress — would make the final decision as to whether an individual should be subject to the 14th Amendment’s lifetime ban.

Chase’s opinion does not formally bind the modern-day Supreme Court. (Chase issued his opinion while “riding circuit”— sitting as a traveling lower-court judge — and so his decision is not technically a Supreme Court precedent.) And not everyone agreed with his view, then or now. U.S. Sen. Lyman Trumbull, a Republican from Illinois and one of the 14th Amendment’s backers, argued that a bill excluding individuals from office was not “punishment” and therefore did not implicate the original Constitution’s proscription against bills of attainder. More recently, Gerard Magliocca, a professor at Indiana University’s McKinney School of Law and an expert on the 14th Amendment’s history, has criticized Chase’s interpretation. “The problem with [Chase’s] approach is that the Fourteenth Amendment was radical in many respects,” Magliocca notes; therefore it may well have overridden elements of the original Constitution, including the bill of attainder ban.

Be that as it may, a law barring Trump from future officeholding that is passed by a simple majority of the House and Senate would raise serious constitutional questions. Trump’s defenders would no doubt argue that the law violates the bill of attainder clause, and unlike many of Trump’s legal arguments, this one would be far from frivolous. Trump could cloak himself in the authority of Chase, an outspoken abolitionist, racial progressive and original member of Abraham Lincoln’s “team of rivals.” It would be an unfortunate irony if Trump, who ran roughshod over individual rights throughout his term, could claim that mantle of civil liberties on his way out.

A better approach would be for Congress to enact a modern-day analogue to the First Ku Klux Klan Act reestablishing a judicial procedure to disqualify insurrectionists. There is, to be sure, a possible argument that the First Ku Klux Klan Act could apply to Trump without reenactment. Even if it does, though, the First Ku Klux Klan Act provides for federal prosecutors to bring civil actions against officeholders — not office-seekers — who are subject to Section 3’s lifetime ban. A legal effort to block a Trump comeback would ideally begin before he (heaven forbid) wins another election.

The new law could authorize federal prosecutors to bring a civil action against anyone who pursues public office in violation of Section 3. Thus if Trump seeks the White House in 2024, the Justice Department could go to court to disqualify him. Trump would have the opportunity to argue for his innocence and present evidence in his defense. The judiciary — not congressional Democrats — would have the ultimate say on whether Trump can run again.

One advantage of this approach is that it will deprive Trump of any claim to the constitutional high ground. Another advantage is that it can plausibly pass in the current Congress. By contrast, using the impeachment process to disqualify Trump from future officeholding is very likely a dead end. Conviction on an impeachment charge requires a two-thirds vote in the Senate, which would mean 17 Republicans would need to cross a president whose grip on that party has been nearly ironclad.

A disadvantage is that this process would take time to play out — possibly years. Any court action to bar Trump from future office will likely be “unripe” — that is, not ready to be heard — unless and until Trump declares his candidacy. So if Trump seeks the White House in the next election, the legal process might not even begin until 2023. (If Trump doesn’t run, the action will never be ripe, but then again, there will be no prospect of a second Trump presidency.)

The choice between the impeachment and Section 3 disqualification isn’t either-or: The House could move first to impeach President Trump, and if the Senate votes to acquit him, then lawmakers could pursue the Section 3 avenue. If and when they do, the better course will be to establish a judicial mechanism for disqualification, rather than seeking to bar Trump by a simple majority vote alone. It may be a long slog, but it will show the respect for constitutional processes that Trump himself so flagrantly lacks.