A divided US Supreme Court has thrown out a judicial decision rejecting Donald Trump’s bid to shield himself from federal criminal charges involving his efforts to overturn his 2020 election loss.

The court ruled that former presidents are shielded from prosecution for actions they take within their constitutional authority, as opposed to a private capacity.

The ruling marked the first time since the nation’s 18th century founding that the Supreme Court has declared that  former presidents may be shielded from criminal charges in any instance.

The decision came in Trump’s appeal of a lower court ruling rejecting his immunity claim. The court decided the blockbuster case on the last day of its term.

Trump hailed the ruling in a social media post, writing: “BIG WIN FOR OUR CONSTITUTION AND DEMOCRACY. PROUD TO BE AN AMERICAN!”

Trump is the Republican candidate challenging Democratic President Joe Biden in the November 5 US election in a rematch from four years ago.

The court’s slow handling of the blockbuster case already had helped Trump by making it unlikely that any trial on these charges brought by Special Counsel Jack Smith could be completed before the election.

Trump had argued that he is immune from prosecution because he was serving as president when he took the actions that led to the charges. Smith had opposed presidential immunity from prosecution based on the principle that no one is above the law.

During April 25 arguments in the case, Trump’s legal team urged the justices to fully shield former presidents from criminal charges – “absolute immunity” – for official acts taken in office.

Without immunity, Trump’s lawyer said, sitting presidents would face “blackmail and extortion” by political rivals due to the threat of future prosecution.

The court’s 6-3 conservative majority includes three justices Trump appointed. Smith’s election subversion charges embody one of the four criminal cases Trump has faced.

Trump, 78, is the first former US president to be criminally prosecuted as well as the first former president convicted of a crime.

In the special counsel’s August 2023 indictment, Trump was charged with conspiring to defraud the United States, corruptly obstructing an official proceeding and conspiring to do so, and conspiring against the right of Americans to vote. He has pleaded not guilty.

Trump’s trial had been scheduled to start on March 4 before the delays over the immunity issue. Now, no trial date is set. Trump made his immunity claim to the trial judge in October, meaning the issue has been litigated for about nine months.

In a separate case brought in New York state court, Trump was found guilty by a jury in Manhattan on May 30 on 34 counts of falsifying documents to cover up hush money paid to a porn star to avoid a sex scandal before the 2016 election. Trump also faces criminal charges in two other cases. He has pleaded not guilty in those and called all the cases against him politically motivated.

A lawyer for the special counsel’s office told the Supreme Court during arguments that the “absolute immunity” sought by Trump would shield presidents from criminal liability for bribery, treason, sedition, murder and, as in this case, trying to overturn the proper results of an election and stay in power.

During the arguments, justices asked hypothetical questions involving a president selling nuclear secrets, taking a bribe or ordering a coup or political assassination. If such actions were official conduct, Trump’s lawyer argued, a former president could be charged only if first impeached by the House of Representatives and convicted in the Senate – something that has never happened in US history.

The timeline of the court’s immunity ruling likely does not leave enough time for Smith to try Trump on federal election subversion charges and for a jury to reach a verdict before voters head to the polls.

Trump also faces election subversion charges in state court in Georgia and federal charges in Florida brought by Smith relating to keeping classified documents after leaving office.

If Trump regains the presidency, he could try to force an end to the prosecution or potentially pardon himself for any federal crimes.