The Supreme Court on Monday overturned a Colorado court ruling that had disqualified former President Donald J. Trump from the state’s primary ballot, concluding that the Constitution does not allow states to invoke the 14th Amendment to bar presidential candidates from seeking office.

The ruling centered on Section 3 of the amendment, which was enacted after the Civil War. The provision bars people from office if they took an oath to uphold the Constitution but then engaged in an insurrection.

Citing Mr. Trump’s attempt to overturn the 2020 election and the events of Jan. 6, 2021, the Colorado Supreme Court disqualified him, but the U.S. Supreme Court ruled that the state court had no authority to take that step.

Here are some highlights.

None of the opinions addressed whether Mr. Trump engaged in insurrection. While the Supreme Court unanimously agreed that states cannot enforce Section 3, the justices split over whether to also say how the federal government may do so.

The main opinion was filed “per curiam,” meaning it was a joint ruling that was not signed by any particular justice.

Five of the conservative justices — Chief Justice John G. Roberts Jr. and Justices Clarence Thomas, Samuel Alito, Neil M. Gorsuch and Brett M. Kavanaugh — agreed with it in its entirety. Its essence was that Section 3 does not empower states to disqualify people seeking federal office, including presidential candidates.