The historic case against Donald Trump faces a number of legal hurdles if it is to result in the first conviction of a US president on criminal charges, legal experts said Wednesday.

As to be expected, Trump's attorneys dismissed the 34-count indictment unsealed on Tuesday at the high-profile arraignment in New York of the 76-year-old real estate tycoon.

"It was a little disappointing, a little bit of a relief quite frankly to see that indictment," Joe Tacopina told NBC's "Today" show. "This case is going to fall on its merits."

Even some of Trump's fiercest critics were not impressed with the case brought by Manhattan District Attorney Alvin Bragg, a Democrat who has been accused by Trump and other Republicans of waging a "political witch hunt."

Trump's former national security adviser John Bolton, who is now one of his most outspoken foes, told CNN the indictment was "even weaker than I feared it would be."

"Speaking as someone who very strongly does not want Donald Trump to get the Republican presidential nomination, I'm extraordinarily distressed by this document," Bolton said.

"I think it's easily subject to being dismissed or a quick acquittal for Trump."

The indictment charges Trump with 34 counts of falsifying business records over a $130,000 hush money payment to porn star Stormy Daniels ahead of the 2016 presidential election.

Trump's personal lawyer Michael Cohen arranged the payment to Daniels and then was reimbursed by Trump in installments, which accounts for the 34 charges.

The payments rise from the level of a misdemeanor to a felony because, the indictment says, they were allegedly made with "intent to commit another crime."

The indictment, however, fails to specify what the other crime was and that's where things may get tricky.

At a press conference, Bragg said the payments were part of a scheme orchestrated by Trump, Cohen and others to "suppress negative information" and boost his election chances.

"The scheme violated New York election law, which makes it a crime to conspire to promote a candidacy by unlawful means," he said.

It's legally questionable, however, whether Trump could be found to have violated New York election law while he was running for president and not for a position in the state.

Ellen Yaroshefsky, a law professor at Hofstra University, said prosecutors may be hard-pressed "to prove that the false business records were with intent to influence the election."

'Disappointment'

Andrew McCabe, a former FBI deputy director, told CNN the indictment was a "disappointment."

"What is the legal theory that ties a very solid misdemeanor case... to the intent to conceal another crime, which is what makes it a felony?" he asked.

"If all of our legal friends read this indictment and don't see a way to a felony, it's hard to imagine convincing a jury that they should get there."

Another potential stumbling block for prosecutors could be Cohen, who was sentenced to prison over the Daniels payments, tax evasion and other crimes.

Cohen's credibility as a witness is certain to come under attack from Trump's lawyers because he is now a convicted felon and a bitter critic of his former boss.

William Banks, a law professor at Syracuse University, said the case was "fraught" with difficulties and the charges pale in comparison to the legal jeopardy Trump could face elsewhere.

Banks specifically cited Georgia, where prosecutors are investigating Trump's efforts to overturn the 2020 election results in the southern state.

A special counsel is also looking into Trump's role in the January 6, 2021, attack on Congress by his supporters and a cache of classified documents taken from the White House to his Florida home.

Richard Hasen, a law professor at the University of California, Los Angeles, said prosecutors would have to prove that Trump knew he was violating campaign finance laws with the payments.

"Proving intent can always be tricky," Hasen wrote in Slate magazine, citing the case of John Edwards, who twice sought the Democratic presidential nomination.

Edwards was put on trial in 2012, accused of campaign finance violations for making hush-money payments to a mistress, but the jury deadlocked.

Not all legal experts were so disparaging of the case.

Barbara McQuade, a former district attorney now teaching at the University of Michigan, said she believed it to be "very solid."

"This case is based largely on documents, which typically make for a very strong case because, unlike witnesses, documents don't lie and documents don't forget," McQuade told AFP.