A grand jury has voted to indict Trump, after months of hearing evidence about a $130,000 payment to porn star Stormy Daniels in the waning days of the 2016 election campaign. The money was intended to buy her silence about the encounter she says they had years before.

The charges were not clear, though legal analysts have said it is likely Trump will be prosecuted for falsifying business records on charges of hiding the true nature of the payments.

Trump has denied Daniels's claim, and his lawyer has accused Daniels, whose real name is Stephanie Clifford, of extortion.

Trump, the first former U.S. president to face criminal prosecution, is leading potential rivals for the Republican nomination, opinion polls show, including Florida Governor Ron DeSantis, who is widely expected to run for the White House.

In the first three quarters of 2022, the average criminal case in Manhattan took more than 900 days to move from indictment to a trial verdict, according to data from the state's division of criminal justice services - and Trump's case is far from typical.

That could push any trial past Election Day in November 2024, though putting a president-elect or president on trial for state charges would enter uncharted legal waters. If elected, he would not hold the power to pardon himself of state charges.

"This is so unprecedented that it's hard for me to say," Karen Friedman Agnifilo, former Manhattan chief assistant district attorney, said when asked earlier this month whether a judge would put Trump on trial close to the election. "I think it's tricky."

The New York case is one of several focused on Trump, including a Georgia election interference probe and a pair of federal investigations into his role in the January 6, 2021, assault on the U.S. Capitol by his supporters trying to overturn his November 2020 election defeat. Another investigation is about his retention of classified documents after leaving the White House.

Challenging the case

In his early career in real estate, as a television celebrity and then in politics, the famously litigious Trump has employed aggressive counter-attacks and delay tactics when confronted with legal challenges.

Trump has accused Manhattan District Attorney Alvin Bragg, an elected Democrat, of targeting him for political gain and could try to seek dismissal of the charges on those grounds.

Trump will likely pursue other avenues as well, some of which could present thorny legal issues that take time to resolve.

Trump's former personal lawyer Michael Cohen has said he coordinated with Trump on the payments to Daniels and to a second woman, former Playboy model Karen McDougal, who also said she had a sexual relationship with him, which Trump has denied.

While president, Trump reimbursed Cohen for the Daniels payments, and federal prosecutors who charged Cohen said in court papers that the payments were falsely recorded as for legal services.

Falsifying business records - the charge that legal analysts say is most likely - is typically a misdemeanour.

To elevate that charge to a felony, prosecutors must prove that Trump falsified records to cover up a second crime. One possibility, according to the New York Times, is that prosecutors could assert the payment itself violated state campaign finance law, since it was effectively an illegal secret donation to boost his campaign.

But using state election law in that manner - and in a case involving a federal, not a state, candidate - is an untested legal theory, legal experts said, and Trump's lawyers would be sure to challenge it.

Trump could also challenge whether the statute of limitations - five years in this instance - should have run out. Under New York law, the statute of limitations can be extended if the defendant has been out of state, but Trump may argue that serving as U.S. president should not apply.

"There's a whole host of possibilities," David Shapiro, a former FBI agent and prosecutor and a lecturer at the John Jay College of Criminal Justice in New York, said before news of the indictment broke. "This is a dream case for defence attorneys."

Fingerprints and mugshot

According to a Bragg spokesperson, prosecutors and Trump's legal team are negotiating a surrender date, when Trump would have to travel from his Florida home to the district attorney's office in New York to be fingerprinted and photographed.

Trump would then make an initial appearance in court, where he would be formally charged. He would likely be allowed to head home afterward, experts said.

The New York Times and NBC News reported that Trump is expected to surrender next week, citing his lawyers. If Trump for some reason decided not to come in voluntarily, prosecutors could seek to have him extradited from Florida.

In an ironic twist, DeSantis would typically have to give formal approval for an extradition demand in his capacity as governor.

In a Twitter post on Thursday, DeSantis said he would not assist in any extradition request, calling the indictment politically motivated. But Florida legal experts said the governor's role in the process is strictly administrative and questioned whether DeSantis can lawfully refuse such a request.

If necessary, experts said, the Manhattan district attorney's office could also go to court to secure Trump's appearance in New York.