A judge has ordered US President Donald Trump to hand over eight years of his tax returns to a New York state criminal investigation.
The judge rejected arguments by the president’s lawyers that total immunity protects him while in office.
Mr Trump is the only presidential candidate since the 1960s apart from Gerald Ford not to release tax returns.
The ruling helps an investigation into hush money paid to two women who claim they had affairs with Mr Trump.
In his 75-page decision on Monday, Judge Victor Marrero said he could not allow a “categorical and limitless assertion of presidential immunity from judicial process”.
“The only thing truly absolute about presidential immunity from criminal process is the Constitution’s silence about the existence and contours of such an exemption,” he wrote.
Judge Marrero concluded that the president’s argument, at its core, was “repugnant to the nation’s governmental structure and constitutional values”.
Mr Trump’s lawyers immediately filed an emergency appeal with a higher court.
The president tweeted about the ruling on Monday, claiming that Democrats were “pushing local New York City and State Democrat prosecutors to go get President Trump”.
What’s the background?
The investigation concerns hush money payments made by Mr Trump’s former lawyer Michael Cohen to two women – adult film star Stormy Daniels and former Playboy model Karen McDougal – who allege affairs with Mr Trump, which he denies.
Manhattan district attorney Cyrus Vance Jr is looking into whether Mr Trump’s organisation broke any election campaign laws by reimbursing Mr Cohen for the payments.
If Judge Marrero’s ruling is not overturned, Mr Vance can enforce an earlier legal demand he issued to Mr Trump’s accountants for the tax returns.
Mr Vance has said that currently, the president “has not been identified as a defendant nor is there an assumption he will be”, according to the Washington Post.
The hush money payments were not reported to the Federal Election Commission during the campaign.
The question is whether the payments were made to protect Mr Trump’s personal reputation or to protect his image as a presidential candidate.
Under US election rules, any payments made with the aim of influencing a vote must be reported.
Mr Cohen this year pleaded guilty to violating laws during the 2016 election over his handling of the hush money, and is currently serving a three-year federal prison sentence for the finance violation and other crimes.
But Mr Trump has insisted the payment was legal and did not come from campaign finances. He has also accused his former fixer of making up stories to receive a lighter sentence.
The Republican president’s lawyers have criticised the investigation as politically motivated.
Democratic President Bill Clinton appointed Judge Marrero in 1999.