The biggest risk our democracy faces this election is whether the votes cast will even matter. Any number of scenarios could play out. Ballots could be (and in fact have already been) lit on fire, or the courts could intervene to throw out votes. But the possibility we should fear the most is the one we still have a chance to prevent: the United States Congress overturning the election.

Donald Trump in 2020 and early 2021 tried to use Congress to do just this, but he also tried so much else that remembering the details is hard. The details, however, are important. Trump’s desperation after losing the election led him to push to disallow votes everywhere he could—browbeating state legislatures, local election boards, state courts, federal courts, and ultimately the U.S. Congress on January 6. It all failed spectacularly, but that was an amateur effort, and one that would have required near-perfect execution to succeed. Joe Biden had won 306 electoral votes to Trump’s 232, meaning that Trump would have had to overturn the results in several states to become president.

This time, the election results might be closer. A tight margin would allow Trump to play in all of the same fora as last time, and now with people who have spent years developing the art of the steal. Even if Trump loses every court case, every attempt to persuade a state governor or state legislature to toss out the popular vote, and every maneuver to try to pressure state and local officials, he may yet use Congress as a backup plan.

[Tyler Austin Harper: Of course Black men are drifting toward Trump]

This is, I suspect, the “big secret” Trump mentioned this week, with a grin, to Speaker of the House Mike Johnson. It’s a secret only because Trump wants to keep it in his back pocket, but it may be quite similar to what he attempted last time. Under laws passed by Congress, including the Electoral Count Act and the 2022 Electoral Count Reform Act, here’s what is supposed to happen:

On January 6, 2025, the House and Senate are to assemble to watch as electoral votes from each state are opened and counted. If a member of Congress has an objection to the vote from any particular state, the objection must be signed by at least 20 percent of the members of both chambers for it to be taken up. Only two categories of objections are permissible: if a state’s electors were not “lawfully certified” (such as if a state certified a fake slate of electors), or if an elector’s vote for a candidate was not “regularly given” (such as if the electors were bribed, voted for an ineligible candidate, or voted in the wrong manner). Otherwise, Congress is to treat a governor’s certification of a slate as “conclusive.” If the 20 percent threshold is met in both chambers, the issue will be debated for up to two hours. Afterward, both the House and the Senate must vote. The objection is sustained if a simple majority supports it in both chambers. If a simple majority in both chambers agrees with an objection to the appointment of a state’s electors as not “lawfully certified,” then that state is excluded from the Electoral College, altering the denominator in the College. (If a particular elector is struck under the “regularly given” provision, by contrast, the denominator does not change.) This means that the number of votes needed to win in the Electoral College drops accordingly when a state’s electors are struck for not being “lawfully certified.” For example, if an objection to Pennsylvania’s slate were sustained, the state’s 19 electoral votes would be eliminated, and winning the presidency would take 260 electoral votes instead of 270.

Congress’s 2022 Reform Act was intended to reduce opportunities for mischief, but even so, mischief may yet emerge. For example, what does “lawfully certified” mean? If Trump claims that undocumented immigrants voted in a state, does that mean the state’s vote was not “lawfully certified”? What about claims that absentee ballots were wrongly counted? Or that ballots arrived late?

The answer to all of these is an unequivocal no. Lawfully certified has long had a much more precise and technical meaning about procedure—simply whether the state’s governor has certified the vote. That narrowness has led some to say that there is nothing to fear, especially because Congress has tightened the rules in the 2022 act and made it harder for Congress to second-guess election results. I very much hope that’s right. It should be right. It is right. But we are living in a world where the whole enterprise and meaning of law is contested, and where politicians stretch laws past their breaking point. James Madison warned us about this in The Federalist Papers, calling law a mere “parchment barrier.” This time, the parchment may not hold.

Here’s how the nightmare scenario could play out. Imagine the election puts Kamala Harris in the lead, with 277 to Trump’s 261 votes. Further imagine that part of that lead comes from Pennsylvania. And then imagine that Pennsylvania decides to count mail-in ballots that are missing the required handwritten date on the envelope. Trump then challenges that practice, claiming that the Pennsylvania legislature has set rules that forbid counting those ballots. He goes through the Pennsylvania courts, all the way to the Pennsylvania Supreme Court, which rejects his challenge and allows the ballots to be counted. Trump then goes to the U.S. Supreme Court, which also rejects his challenge.

Although that should be the end of the madness, it may not be. On January 6, one-fifth of the House and one-fifth of the Senate can claim that the Pennsylvania Supreme Court acted improperly by counting these ballots, in defiance of state law. They can assert that they have the right to interpret the law independently, and that Pennsylvania has acted lawlessly. The good news here is that Congress in 2022 foreclosed that independent congressional-determination route, and said that court decisions are binding on Congress when it acts on January 6. But there is room for tendentious arguments about what Congress actually legislated, and some (including Senator Ted Cruz) have already said they believe that the 2022 act is unconstitutional. So despite Congress’s very strong 2022 efforts in this regard, an unprincipled House and Senate could try to assert these powers. The assertion of such powers would be bogus, but a debate on the floor would then ensue, and if a raw majority of the House and Senate sustain the objection—no matter how specious it is—Pennsylvania’s 19 electoral votes would be struck, leaving 258 electoral votes for Harris and 260 for Trump. Trump would then be declared the president.

Such a decision could and should be contested in court, and challenged all the way to the United States Supreme Court, where the challenge should win. Congress would be defying the parts of the 2022 law that tightly restricted the types of objections, as well as provisions in the law that make court determinations conclusive on Congress. The question is, if Congress acts lawlessly, what will the Supreme Court do about it? Some are pointing to the Court’s recent decision to permit Virginia to strike 1,600 individuals from the voting rolls as evidence of its politicization, but defenders of the Court can point to the fact that it stayed out of the mischief in 2020, with hopes that it will act responsibly again in this go-round. The situations are, however, different. The 2020 request was on the part of the mischief makers, asking for the Court to affirmatively intervene in Trump’s favor—something the Court was apparently loath to do. This time, nonintervention favors Trump. The Court can say it is acting neutrally by not hearing the case and, by doing so, effectively hand the presidency to Trump in defiance of the will of the people.

[Read: The Democratic theory of winning with less]

The Supreme Court, of course, is fully capable of realizing the difference between affirmatively intervening in 2020 (where it was being asked to facilitate Trump’s theft of the election) and 2024 (where it would be asked to prevent such a thing). A decision to stay out in the face of congressional lawlessness should be unthinkable. And let us hope that it is (recall the Court just last year in Moore v. Harper rejected, by a 6–3 vote, a Republican Party theory that would have given it an immense advantage in federal elections). But just in case, one important thing must be done to prevent this nightmare from unfolding: vote.

If as a result of the vote on November 5, Harris claims a decisive victory in the Electoral College, then there is little to fear, much as Trump might try to fight it. And even if the Electoral College is close, remember that Americans also vote for the House and the Senate on November 5. And the new House and Senate, not the existing ones, will make all of the decisions outlined above on January 6, 2025. If the Democrats control the House, or hold the Senate, this divided government will prevent the nightmare scenario from coming to fruition. And even if the Republicans control both houses in 2025, electing people who will honor the language and purpose of the 2022 Electoral Count Reform Act—which, again, was written to prevent this scenario—will put an end to the madness.

So when you vote, vote for candidates who will ensure that the will of the people will govern. James Madison in “Federalist No. 55” reminds us that the “degree of depravity in mankind … requires a certain degree of … distrust,” but “there are other qualities in human nature which justify a certain portion of esteem and confidence.” Republican government, Madison went on, depends on the latter. Let us pray that those qualities lead Americans to the polls on Tuesday and, once there, that they vote to protect our democracy.