Donald Trump has become the first former president to be indicted in a criminal case after a grand jury investigation into hush money payments made on his behalf during the 2016 presidential campaign.

The unprecedented indictment comes as the Republican faces other legal investigations and launches a bid to return to the White House in 2024.

The indictment will test the Republican Party already divided over whether to support Trump next year, in part due to his efforts to undermine his 2020 election loss.

Trump has denied any wrongdoing and accuses prosecutors of engaging in a politically motivated "witch hunt" to damage his campaign.

Here's a look at the hush money case, the grand jury investigation and possible ramifications for Trump's presidential campaign:

WHAT'S THIS CASE ABOUT?

The New York grand jury spent weeks meeting in secret to probe Trump's involvement in a $130,000 payment made in 2016 to the porn actor Stormy Daniels to keep her from going public about a sexual encounter she said she had with him years earlier. Trump lawyer Michael Cohen paid Daniels, whose real name is Stephanie Clifford, through a shell company before being reimbursed by Trump, whose company, the Trump Organization, logged the reimbursements as legal expenses.

Earlier in 2016, Cohen also arranged for former Playboy model Karen McDougal to be paid $150,000 by the publisher of the supermarket tabloid The National Enquirer, which then squelched her story in a journalistically dubious practice known as "catch and kill."

Trump denies having sex with either woman.

Trump's company "grossed up" Cohen's reimbursement for the Daniels payment to defray tax payments, according to federal prosecutors who filed criminal charges against the lawyer in connection with the payments in 2018. In all, Cohen got $360,000 plus a $60,000 bonus, for a total of $420,000.

Cohen pleaded guilty to violating federal campaign finance law in connection with the payments. Federal prosecutors say the payments amounted to illegal, unreported assistance to Trump's campaign. But they declined to file charges against Trump himself.

WHAT'S AN INDICTMENT?

An indictment is the formal charge brought against someone after a grand jury — which is made up of members of the community — votes and enough members agree there's sufficient evidence to charge someone with a crime.

The indictment against Trump remains sealed, as is standard in New York before an arraignment. But once the document is made public, it will lay out the crime or crimes that Trump is accused of committing. Sometimes indictments include a lengthy narrative with lots of details about the allegations, while others are more basic and just outline the charges a defendant is facing.

WHAT ARE THE CHARGES?

The indictment has not yet been unsealed, so it's not totally clear.

Some experts have said they believe Trump could be charged with falsifying business records, which can be a misdemeanor or a felony under New York law. To secure a conviction on the felony charge, prosecutors would have to prove that records were falsified with the intention of committing or concealing a second crime. It's not clear what prosecutors may allege as the second crime.

WHAT HAS TRUMP'S LAWYER SAID?

Trump's lawyer, Joe Tacopina, said Thursday that the former president didn't commit any crime and vowed to "vigorously fight this political prosecution in court."

Tacopina has accused prosecutors of "distorting laws" to try to take down the former president. He has described Trump as a victim of extortion who had to pay the money because the allegations were going to be embarrassing to him "regardless of the campaign."

"He made this with personal funds to prevent something from coming out — false, but embarrassing to himself, his family, his young son. That's not a campaign finance violation, not by any stretch," Tacopina said on ABC's "Good Morning America" before the indictment.

WHAT'S THIS GRAND JURY AND WHO TESTIFIED?

A grand jury is made up of people drawn from the community, similar to a trial jury. But unlike juries that hear trials, grand juries don't decide whether someone is guilty or innocent. They only decide whether there is enough evidence for someone to be charged.

Proceedings are closed to the public, including the media. New York grand juries have 23 people. At least 16 must be present to hear evidence or deliberate and 12 have to agree there is enough evidence in order to issue an indictment.

David Pecker, a longtime Trump friend and the former chief executive of the parent company of The National Enquirer, returned to the courthouse this week where the grand jury was meeting.

Pecker's company, American Media Inc., secretly assisted Trump's campaign by paying $150,000 to McDougal in August 2016 for the rights to her story about an alleged affair with Trump. The company then suppressed McDougal's story until after the election.

The grand jury also heard from Cohen, as well as Robert Costello, who was once a legal adviser to Cohen.

The men have since had a falling out, and Costello indicated he has information he believes undercuts Cohen's credibility and contradicts his incriminating statements about Trump. Costello testified at the invitation of prosecutors, presumably as a way to ensure that the grand jury had an opportunity to consider any testimony or evidence that might weaken the case for moving forward with an indictment.

Trump was also invited to testify, but didn't.

WHAT HAPPENS NEXT?

Law enforcement officials have been making security preparations for days for the possibility of an indictment and a court appearance by the president.

Trump is expected to turn himself in and make his first court appearance for his arraignment on Tuesday. When he turns himself in, he isn't expected to be put in handcuffs, according to a person familiar with the matter. Secret Service agents assigned to him will escort him through the booking process at the Manhattan district attorney's office, but prosecutors have no plans to shackle Trump's hands during it, the person said.

WHAT ARE THE POLITICAL RAMIFICATIONS FOR TRUMP?

Neither the indictment itself nor a conviction would prevent Trump from running for or winning the presidency in 2024.

Last week in Waco, Texas, Trump took a defiant stance at a rally by disparaging the prosecutors investigating him and predicting his vindication as he rallied supporters in a city made famous by deadly resistance against law enforcement.

"You will be vindicated and proud," Trump said in a speech brimming with resentments and framing the probes as political attacks on himself and his followers. "The thugs and criminals who are corrupting our justice system will be defeated, discredited and totally disgraced."

Before the charges were handed down, many party leaders had also already begun to defend the former president.

During a visit this month to Iowa, former Vice President Mike Pence called the idea of indicting a former president "deeply troubling." Another 2024 Republican prospect, New Hampshire Gov. Chris Sununu, has said there is a sense that the former president is being unfairly attacked.

Former South Carolina Gov. Nikki Haley, a declared candidate who also served as Trump's U.N. ambassador, has called Bragg's case an attempt at scoring "political points," adding, "You never want to condone any sort of prosecution that's being politicized."

Florida Gov. Ron DeSantis, who is considering joining the 2024 Republican field, slammed the investigation as politically motivated. But he also threw one of his first jabs at the former president in a quip likely to intensify their rivalry. DeSantis said he personally doesn't "know what goes into paying hush money to a porn star to secure silence over some kind of alleged affair."

WHAT ABOUT OTHER TRUMP INVESTIGATIONS?

The New York case is just one of many legal woes Trump is facing.

The Justice Department is also investigating his retention of top secret government documents at his Florida estate, Mar-a-Lago, after leaving the White House. Federal investigators are also still probing the Jan. 6, 2021, insurrection at the U.S. Capitol and efforts to overturn the 2020 election that Trump falsely claimed was stolen.

In Georgia, Fulton County District Attorney Fani Willis has been investigating whether Trump and his allies illegally meddled in the 2020 election. The foreperson of a special grand jury, which heard from dozens of witnesses, said last month that the panel had recommended that numerous people be indicted, and hinted Trump could be among them. It is ultimately up to Willis to decide whether to move forward.

____

Associated Press reporters Michael R. Sisak and Mike Balsamo contributed.