Donald Trump indictment: What happened today and what's next?

After days of intense speculation, it's finally happened: former US president Donald Trump has been indicted by a grand jury.

He will be the first former president in US history to face criminal charges.

The exact details of what he's being charged with are not yet known because grand jury proceedings in the US remain secret until the defendant is in custody.

But we know the hearings focused on an alleged hush money payment made to adult performer Stormy Daniels in 2016.

So what happens now? Will he have to pose for a mugshot?

Here's what we know so far.

What just happened?

Grand jury proceedings happen almost entirely in secret.

But it's believed this jury was asked to decide whether it was illegal for Trump to order his former fixer Michael Cohen to pay Daniels for her silence.

In 2016, when Trump was running for presidency, the adult star went public with her claim that she had sex with him when he was married.

Cohen alleged he was directed to give her $US130,000 (NZD$206,804) and conceal the nature of the payment as a legal expense.

Trump's lawyers have been alerted that the grand jury voted to indict their client.

Now they have to arrange a surrender.

In a statement, Trump declared "this is political persecution and election interference at the highest level in history", describing the charges as part of a "witch hunt" by "the radical left".

Our corrupt elites aren't threatened by violent criminals on the streets because all of them have private security. They don't care if normal people are being terrorized. But they are threatened by Trump, which is why they're willing to turn us into a Banana Republic to stop him! https://t.co/y5TdrdT2K7

— Donald Trump Jr. (@DonaldJTrumpJr) March 30, 2023

He proclaimed his innocence, but did not make any direct appeals for his supporters to protest in the streets, as he had done on Truth Social last week.

But he did take direct aim at the Manhattan District Attorney Alvin Bragg, who has been overseeing the case.

Authorities in New York City have been bracing for unrest, bolstering security around the DA's office.

Trump has to get to New York City

An indictment is basically a formal notice of criminal charges, but it does not mean there is a warrant out for Trump's arrest

In some cases, defendants are offered the opportunity to turn themselves over for voluntary processing, a common practice in white collar investigations in the US.

The New York District Attorney's office has confirmed it has contacted Trump's attorneys to coordinate his surrender.

One of his lawyers, Susan R Necheles told the New York Times Trump will turn himself in on Tuesday.

An arrest warrant would only be issued if Trump failed to appear.

It is likely his legal team will negotiate with prosecutors over the coming days about the terms of the former president's arraignment.

Trump is currently residing at his sprawling Mar-a-Lago home in Florida, so as part of that process he will have to make his way to New York City.

He could arrange to fly there on his private jet and make the journey to the Manhattan court house by car to avoid a public spectacle.

Some legal experts have expressed doubts about Trump performing a "perp walk" in front of a crowd of gathered media.

What if Trump refuses to surrender?

In the unlikely scenario that Trump refuses to cooperate with authorities and surrender, he may choose to hunker down at Mar-a-Lago.

Officials would need to negotiate with Florida for permission to extradite the former president to New York.

This puts governor Ron De Santis, who is anticipated to run against Trump for Republican presidential candidate in 2024, in an awkward position.

While the governor told reporters last week he had "no interest in getting involved" in Trump's indictment, today he announced on Twitter that Florida "will not assist" in an extradition request.

The weaponization of the legal system to advance a political agenda turns the rule of law on its head.

It is un-American.

The Soros-backed Manhattan District Attorney has consistently bent the law to downgrade felonies and to excuse criminal misconduct. Yet, now he is…

— Ron DeSantis (@GovRonDeSantis) March 30, 2023

DeSantis has likely been weighing up potential damage to his brand among Trump loyalists and Republican voters if he were to allow the arrest, against the consequences of getting involved.

Florida law appears to leave some wiggle room for the governor to intervene in extradition requests from other states, but legal experts have warned that the US constitution overrides this loophole.

In any event, it appears likely that Trump would eventually be extradited back to New York.

Trump will be fingerprinted, and pose for a mug shot

Once Trump arrives at the New York court house, he will be processed as a defendant.

He will be fingerprinted and photographed, and read his Miranda rights. This is when the police officer tells a detained suspect that they have the right to remain silent.

Trump will then wait in a holding cell to be called before a judge to enter a plea in what's called an arraignment - which will be open to the public.

Trump will be accompanied by Secret Service agents throughout the process, but it's not yet clear if security will be ramped up in the courthouse following his surrender.

The chief spokesperson for the Secret Service would not comment on any specific measures made for Trump when approached by the New York Times.

Once he is arraigned, the felony indictment will be unsealed - if it hasn't been already made public - and the charges against the former president will be laid out.

He will enter a plea and the next stages of the court proceedings will be set.

It's likely Trump will be released on his own recognisance, which means he will get bail without having to pay a bond.

How will Trump plead and could he face jail time?

If the former president pleads guilty, the case will proceed directly to sentencing.

Given he has publicly maintained his innocence in the lead-up to this indictment, it appears more likely Trump will plead not guilty, which would mean the case proceeds to trial.

It could take more than a year for the trial to begin, according to a former Manhattan chief assistant DA who spoke to Reuters.

If Trump is found not guilty, he would be acquitted.

If he is convicted, the sentence depends entirely on the charges, which have not yet been confirmed.

Ahead of the indictment, legal experts speculated that Bragg may be considering charges related to falsifying business records with the intent to conceal another crime, likely related to campaign finances.

This would be considered a low-level felony, with a maximum sentence of four years in prison.

However, it is entirely possible the charges could be downgraded, or a lesser sentence handed down.

This means even if Trump is convicted of a felony charge, he may not spend any time in jail.

In any event, a conviction would not legally prevent Trump from running for president again in 2024, though the pending case may complicate his campaign.

- ABC