Trump's eligibility for the ballot is being challenged under the 14th Amendment. Here are the notable cases.

Washington — Decisions in Maine and Colorado finding that former President Donald Trump is disqualified from holding public office have rested on a 155-year-old constitutional provision that was seldom used in modern times, but has now been invoked in escalating legal challenges from across the country targeting Trump's eligibility to hold the presidency again.

The efforts aimed at Trump's ability to appear on ballots under the Constitution's so-called insurrection clause, Section 3 of the 14th Amendment, began just months after the Jan. 6, 2021, attack on the U.S. Capitol. That's when the liberal advocacy group Free Speech for People sent letters to the top election officials in all 50 states urging them to bar the former president from the ballot as a candidate for the White House in 2024.

Since then, legal challenges to Trump's eligibility under the measure have been brought in federal and state courts in more than two dozen states — 26 cases were filed by a little-known Republican presidential candidate named John Anthony Castro. Most cases brought by Castro have been dismissed, either voluntarily or by the courts. In 14 states, there are cases pending, according to Lawfare, a national security website that is tracking the Section 3 cases.

But in Colorado, a case brought by a group of voters became the first victory in the effort against Trump, when the state Supreme Court found he is disqualified from holding office again.

In a handful of other states, secretaries of state have said they cannot unilaterally remove Trump from the ballot. But Maine's secretary of state became the first to do so Thursday night, when she issued a decision finding that Trump is not qualified to hold the presidency because of his conduct surrounding the Jan. 6 attack and should be removed from the primary ballot.

The Colorado and Maine challenges have been the only ones to succeed in declaring Trump ineligible under Section 3, though the question of whether he can appear on the 2024 ballot is likely to be decided by the U.S. Supreme Court. 

Here are the other states where noteworthy efforts have been underway to keep Trump off their primary ballots:

California

Shortly after the Colorado Supreme Court ruled that Trump is disqualified from holding the presidency under Section 3, California's lieutenant governor asked the secretary of state to explore "every legal option" to remove Trump from the state's primary ballot.

"California must stand on the right side of history," Lt. Gov. Eleni Kounalakis wrote to Secretary of State Shirley Weber in a Dec. 20 letter. "California is obligated to determine if Trump is ineligible for the California ballot for the same reasons described in Anderson (the Colorado case). The Colorado decision can be the basis for a similar decision here in our state. The constitution is clear: you must be 35 years old and not be an insurrectionist."

In response, Weber told Kounalakis in a letter last week that there are "complex legal issues surrounding this matter," and said any decision on whether to list Trump on the primary ballot must "be grounded firmly in the laws and processes in place in California and our Constitution." Both Kounalakis and Weber are Democrats.

Trump's name will appear on the state's primary ballot, as Weber released on Thursday night a certified list of presidential candidates for California's March 5 primary that included the former president.

Colorado

In a landmark decision on Dec. 19, the Colorado Supreme Court found that Trump is disqualified from holding public office again under Section 3 of the 14th Amendment. The divided 4-3 court ruled against Trump on all of the key legal issues it weighed, including that Section 3 covers the presidency and those who swore the presidential oath, that the Jan. 6 attack on the Capitol constituted an insurrection, and that Trump "engaged in" insurrection.

The state Supreme Court's majority ordered the secretary of state to exclude his name from the presidential primary ballot, but put its decision on hold until Jan. 4 to allow Trump to appeal to the U.S. Supreme Court. The Colorado Republican Party, which intervened in the case, asked the nation's highest court to review the Colorado Supreme Court's decision on Wednesday.

The appeal by the Colorado GOP means Trump will be included as a candidate on Colorado's primary ballot unless the U.S. Supreme Court declines to hear the case or upholds the state Supreme Court's ruling, the secretary of state said.

The Colorado Supreme Court, composed of seven justices appointed by Democratic governors, is the first to remove Trump from a presidential primary ballot, and its decision marks the first time a presidential candidate has been deemed ineligible for the White House under Section 3.

Maine

Maine law requires challenges to a primary nomination to be filed with the secretary of state, who then holds a public hearing where the challengers must make their case as to why the primary nomination petition should be invalidated.

Secretary of State Shenna Bellows received three challenges to Trump's primary nomination petition, two of which argued that the former president doesn't meet the qualifications for the presidency and is ineligible to hold public office under Section 3.

Bellows, a Democrat, held a hearing on the bids to remove Trump's name from the primary ballot on Dec. 15 and issued her decision Thursday, finding that the former president is disqualified from holding office again because of his actions surrounding the Jan. 6 riot.

"I am mindful that no secretary of state has ever deprived a presidential candidate of ballot access based on Section Three of the Fourteenth Amendment," Bellows wrote in her 34-page decision. "I am also mindful, however, that no presidential candidate has ever before engaged in insurrection."

Trump can appeal in state court, and Bellows suspended the effect of her decision until the court rules on any appeal. Maine's highest court, the Supreme Judicial Court, can also be asked to review any ruling by a lower court. The case may ultimately be decided by the U.S. Supreme Court.

Michigan

The Michigan Supreme Court on Wednesday declined to review a state Court of Appeals decision that allowed Trump to remain on the state's presidential primary ballot.

The state's high court said in a brief, unsigned order that it is "not persuaded that the questions presented should be reviewed by this court." There was no vote count included in the order.

The challenge to Trump's candidacy in Michigan was brought by four voters on behalf of the liberal advocacy group Free Speech for People, which is behind similar cases in Oregon and Minnesota. The group of voters argued that Trump cannot hold office because of his conduct surrounding the Jan. 6 attack.

A Michigan Court of Claims judge dismissed the case on technical grounds, finding in part that it involved a political question that cannot be decided by the courts and that the political parties determine their presidential candidates for the primary. A three-judge Court of Appeals panel upheld the lower court's ruling and said the political parties and individual candidates determine who to list on the primary ballot. All three judges on the panel were appointed by former Republican Gov. Rick Snyder.

The appeals court's decision, though, does not block voters from renewing a challenge to Trump's candidacy for the general election ballot if he wins the Republican presidential nomination.

Minnesota

Minnesota's Supreme Court tossed out a case brought by eight voters in the state who sought to have Trump's name kept off the primary ballot. The high court said that while the Minnesota secretary of state and other election officials administer the election, the primary is an "internal party election to serve internal party purposes."

"There is no state statute that prohibits a major political party from placing on the presidential nomination primary ballot, or sending delegates to the national convention supporting, a candidate who is ineligible to hold office," the Minnesota Supreme Court found.

The court, though, said the voters could renew their challenge for the general election.

New Hampshire

Trump's name will be listed on the primary ballot in New Hampshire after the state's top election official, Secretary of State David Scanlan, said in September that there is no legal basis for excluding the former president.

"There is no mention in New Hampshire state statute that a candidate in a new presidential primary can be disqualified using the 14th Amendment of the United States Constitution referencing insurrection or rebellion," Scanlan said during a news conference. "Similarly, there is nothing in the 14th Amendment that suggests that exercising the provisions of that amendment should take place during the delegate selection process held by the different states."

Scanlan, a Republican, said that the language of state election law "is not discretionary," and any candidate who pays a $1,000 filing fee and signs a declaration of candidacy swearing that they meet age, citizenship and residency requirements will have their name listed on ballots.

The secretary of state had asked New Hampshire Attorney General John Formella in August to advise on the meaning of Section 3 and its potential applicability to the 2024 election cycle. Formella, a Republican, issued his guidance in mid-September, saying state law doesn't give the secretary of state discretion to withhold a primary candidate's name from the ballot "on the grounds that the candidate may be disqualified under Section 3 when a candidate has not been convicted or otherwise adjudicated guilty of conduct that would disqualify" them under the provision.

Oregon

Oregon Secretary of State LaVonne Griffin-Valade said in late November that she would not remove Trump from the ballot for the Republican presidential primary because state law does not give her the authority to determine a candidate's qualifications.

The announcement from Griffin-Valade, who was appointed by Democratic Gov. Tina Kotek earlier this year, came after Oregon's solicitor general, Benjamin Gutman, determined that Oregon law doesn't charge the secretary of state with determining whether a primary candidate will be qualified to serve as president if elected. Section 3, Gutman wrote in a letter to Griffin-Valade, "does not prevent placing a candidate on the presidential primary ballot."

Gutman, who serves in a Democratic-led administration, stressed that his guidance is limited to the secretary's responsibility as to the primary ballot and said the question of Trump's eligibility may arise again with respect to the general election if he receives the Republican presidential nomination.

Griffin-Valade, too, noted that her decision not to exclude Trump from the ballot applies only to the primary and not the November general election.

Still, five voters in Oregon asked the state Supreme Court earlier this month to order Griffin-Valade to disqualify Trump from both the primary and general election ballots, arguing he is constitutionally ineligible for the presidency. 

The other states

Cases in 14 states arguing Trump is not eligible remain pending. Those states are: Alaska, Arizona, Nevada, New Jersey, New Mexico, New York, Oregon, South Carolina, Texas, Vermont, Virginia, West Virginia, Wisconsin and Wyoming, according to Lawfare's database.

In Arizona, a lower court decision dismissing the case has been appealed. 

In:
• 14th Amendment
• Donald Trump
• Election
• United States Constitution

Melissa Quinn

Melissa Quinn is a politics reporter for CBSNews.com. She has written for outlets including the Washington Examiner, Daily Signal and Alexandria Times. Melissa covers U.S. politics, with a focus on the Supreme Court and federal courts.

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