US Supreme Court justices on Thursday appeared to put in doubt a state's ballot ban against Donald Trump, in a landmark hearing of arguments on his eligibility to be on the 2024 presidential ballot.
It marked the first time in US history that Section 3 of the 14th Amendment had been used to disqualify a presidential candidate.
The Civil War-era amendment was first adopted in the late 1800s to prevent former Confederates who “engaged in insurrection or rebellion” from holding office.
The hearing placed the Supreme Court at the centre of the 2024 US election, conjuring memories of when it was asked to decide on the Bush v Gore decision in 2000 that eventually handed George W Bush the presidency.
In an argument session that lasted just over two hours, liberal and conservative justices questioned whether the Colorado Supreme Court had power to exclude Mr Trump on the grounds that he engaged in an insurrection.
“Why should a single state have the ability to make this determination, not only for their own citizens but for the rest of the nation?” asked Justice Elena Kagan.
Their main concern was whether Congress must act before states can invoke a constitutional provision that was adopted after the Civil War to prevent former officeholders who “engaged in insurrection” from holding office again.
Mr Trump's lawyer Jonathan Mitchell said that if a state banned “even an admitted insurrectionist from the ballot, it would be adding to and altering the Constitution's qualifications for office”.
“If the candidate is an admitted insurrectionist, Section 3 still allows the candidate to run for office and even win election to office – and then see whether Congress lifts that disability after the election,” Mr Mitchell said.
Chief Justice John Roberts expressed concern over the "daunting consequence" of upholding the state court ruling.
"If Colorado's position is upheld, surely there will be disqualification proceedings on the other side," Mr Roberts said.
"I would expect that a goodly number of states will say, 'Whoever the Democratic candidate is, you're off the ballot.'
"It will come down to just a handful of states that are going to decide the presidential election."
Lawyer Jason Murray, representing the voters, pressed the point that Mr Trump incited the Capitol attack to prevent the peaceful handover of power “for the first time in history".
Colorado Solicitor General Shannon Stevenson said in response: "I think we need to have faith in our system."
The former president did not attend the hearing.
Mr Trump, speaking to reporters after the proceedings, called the Supreme Court argument “a beautiful thing to watch in many respects", even as he complained about the case being brought in the first place.
“I hope that democracy in this country will continue,” he said at his Mar-a-Lago club in Florida.
There also were questions about whether a president is covered by the provision.
Questioned by liberal Justice Ketanji Brown Jackson, Mr Mitchell said that Mr Trump is not subject to the disqualification terms because a president is not an “officer of the United States”.
Mr Mitchell said such an officer would only be an appointed official.
The Supreme Court's decision will have significant ramifications for the 2024 election. Siding with Mr Trump will end efforts in Maine and elsewhere to prevent him from appearing on the ballot.
“The consequences of what the Colorado Supreme Court did, some people claim, would be quite severe,” said conservative Justice Samuel Alito.
“The decision of the Colorado Supreme Court could effectively decide this question for many other states, perhaps all other states.”
Should the US Supreme Court determine that Mr Trump is barred from holding office again, states would be allowed to keep him off the ballot.
The case will probably not be the only one involving the former president that the court will be asked to hear.
Mr Trump is also expected to appeal against lower court rulings that he is not immune from criminal prosecution.