The news that Manhattan’s district attorney has convened a special grand jury as part of his criminal probe of former President Trump’s business dealings has fueled speculation over whether he could become the first U.S. president to serve prison time.

Legal experts said the development indicates that Manhattan District Attorney Cy Vance Jr. is moving closer to pursuing criminal charges of some kind. But with so much still unknown, they cautioned against reading too much into what Vance’s move might ultimately mean for the former president.

“By empaneling the special grand jury, Vance has indicated he found significant evidence of one or more crimes by one or more people and is preparing to present evidence to secure indictments,” said attorney and legal analyst Bradley Moss.   

“Whether he will ultimately obtain those indictments, and against whom within the Trump Organization, remains to be seen,” Moss added. “People leaping to the conclusion that this means former President Trump is headed for jail any time soon need to slow their roll.”

Vance’s wide-ranging inquiry is reportedly interested in hush money payments to Trump’s alleged mistresses, questionable valuations of Trump Organization assets and employee compensation arrangements that may have skirted taxes.

It’s unclear which if any of these investigative dimensions might have triggered Vance’s decision to convene a special grand jury, though experts said such panels are typically formed in order to drill more deeply into complex legal matters.

“Special grand juries are typically empaneled for longer periods of time and meet more regularly than a normal grand jury, and they do so because special grand juries primarily are empaneled for complex cases,” Moss said.

The panel that Vance has convened will gather three days a week for six months, according to The Washington Post, which was first to report the new development.

Broadly speaking, grand juries serve as both a prosecutor’s investigative tool and as a gatekeeper for determining whether to issue formal accusations of criminal wrongdoing in the form of indictments. 

Vance has previously relied on a regular grand jury’s subpoena power to aid his criminal investigation of Trump’s business dealings. In August 2019, he obtained a grand jury subpoena for Trump’s tax returns.

After a lengthy legal battle, Vance’s office in February received eight years’ worth of Trump’s tax returns, which are said to number in the millions of pages.

David Fahrenthold, one of the Post reporters who broke the news Monday that Vance had convened a special grand jury, said that “the timing of this was all about the tax returns.”  

“Vance had made the decision to ask for everything, and he couldn’t move until he got the tax returns,” Fahrenthold told MSNBC. “Once he got them, he’s had some forensic accountants, he's had a lot of prosecutors going through them. They've had a few months. We don't know how far in they are, but I imagine they've already learned a lot.”

News of the special grand jury’s formation is just one of several recent signs that the investigation into Trump’s financial activity is ramping up. Vance’s two-year probe had been unfolding in parallel to an overlapping inquiry by New York Attorney General Letitia James. But last week James revealed the two investigations had converged and that the offices are now coordinating efforts.

Trump, for his part, has dismissed the investigations as a partisan “witch hunt.”

“This is purely political, and an affront to the almost 75 million voters who supported me in the Presidential Election, and it’s being driven by highly partisan Democrat prosecutors,” he said in a statement.

Vance's criminal probe opened in 2019 to look into payments made to silence two women including porn star Stormy Daniels who allege they had affairs with Trump, which he has denied. Trump’s former lawyer and fixer Michael Cohen, who served prison time in part for his role in the payoff scheme, which violated campaign finance laws, said he conducted the payments at Trump’s direction in order to influence the 2016 presidential election. 

Another theory prosecutors are reportedly pursuing is that the Trump Organization inflated the value of assets to get more favorable terms for bank loans, insurance and tax breaks and deflated the value of those same assets to reduce the amount owed in real estate taxes.

Investigators are also said to be looking into whether Trump’s business gave employees benefits instead of higher salaries as a way to lower the company’s payroll tax burden. Tax law generally considers employee perks to be taxable, which companies are responsible for paying. 

Among the alleged beneficiaries are Trump’s longtime chief financial officer Allen Weisselberg and his family members, who reportedly received heavily discounted or free access to Trump-owned apartments in Manhattan and other perks.

Prosecutors reportedly aim to “flip” Weisselberg, meaning gain his cooperation as a witness against the former president and his company. As a top Trump executive for four decades, Weisselberg is thought to be a potentially key source of information for investigators, including the extent to which the company's fringe benefits went unreported to the Internal Revenue Service.

Jennifer Weisselberg, the former daughter-in-law of Trump’s financial chief, has said she believes that Trump paid for one of her two children’s tuition to an upscale Manhattan private school that costs $54,000 annually per child (and said Allen Weisselberg paid for the other child). 

Vance's office has reportedly subpoenaed the school for tuition payment records, as well as records from Weisselberg’s bank.