Prosecutors in New York who have been probing more than $350 million in loans Donald Trump took out on Trump Tower and three other Manhattan properties are honing in on allegations of financial crimes.

The years-old criminal investigation has made the former US president vulnerable to prosecution despite being acquitted at his second impeachment trial.

Property records show Mr Trump was loaned more than $US280 million ($A361 million) for four Manhattan buildings that prosecutors believe could possibly reveal “extensive and protracted criminal conduct at the Trump Organisation”.

The properties in question are Trump Tower on Fifth Avenue; a skyscraper at 40 Wall Street; a hotel and residential building on Columbus Circle near Central Park; and an apartment building on the Upper East Side.

Inside the Trump Tower atrium. Photo: Getty

The loans were made to Mr Trump by companies connected to New York City real estate investment trust, Ladder Capital Corp.

Mr Trump is in the spotlight for allegedly making dodgy deals in which he kept two sets of record-keeping books, giving one set of figures to his lenders and a different set to tax authorities.

A decision is imminent on whether District Attorney Cyrus Vance can access Mr Trump’s tax records.

He is one of the investigators who are looking to see if what’s on the former president’s tax records differ from what’s on his financial statements.

There are concerns Mr Trump gave out fake information on his loan applications to get the loans for the four buildings approved.

Mr Trump faces a swathe of other legal problems now that he’s out of the White House.

He’s staring down the barrel of at least two state-level investigations – one in New York, the other in Georgia – as well as criminal charges for his role in the Capitol Hill riots.

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And this time, he won’t have nearly as many Republicans going in to bat for him.

Quite the opposite.

Despite the majority of Republican senators voting to acquit Mr Trump in the impeachment trial, many of them expressed outrage at the former president’s involvement in the Capitol Hill riots and pointed to the court system as an avenue for further prosecution.

“The ultimate accountability is through our criminal justice system where political passions are checked,” said Republican senator Thom Tillis, who voted not guilty.

“No president is above the law or immune from criminal prosecution, and that includes former president Trump.”

Mitch McConnell slammed Mr Trump for his role in encouraging the insurrection.

Minority leader Mitch McConnell, who also voted to acquit, slammed Mr Trump for his role in encouraging the insurrection at Capitol Hill.

“Impeachment was never meant to be the final forum for American justice,” he told the Senate.

“We have a criminal justice system in this country. We have civil litigation. And former presidents are not immune from being held accountable by either one.”

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From the outset, this position might seem like a convenient way for Republicans to evade responsibility.

But the threat of criminal prosecution is a real possibility for Mr Trump.

Here are the incidents that he’s under investigation for.

Inciting the Capitol Hill riots

An army brimming with hate and fury, rioters storm Capitol Hill. Photo: AP

The former president has reportedly voiced concerns about being prosecuted for his role in the January 6 riot, according to CNN. 

That’s when he implored his followers to “fight like hell … or you’re not going to have a country any more” shortly before they stormed the Capitol.

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Acting US Attorney Michael Sherwin said authorities were “looking at all actors” responsible for the attack, and “if the evidence fits the elements of the crime, they’re going to be charged”.

Pressuring Georgia state officials to flip the vote

Both Georgia’s Secretary of State Brad Raffensperger and Fulton County district attorney Fani Willis are investigating Mr Trump’s efforts to pressure state officials to “find 11,780 votes” to flip the state during the presidential election.

Mr Trump’s phone calls may have violated at least three state criminal election laws:

• Conspiracy to commit election fraud
• Criminal solicitation to commit election fraud; and
• Intentional interference with performance of election duties.

The criminal and misdemeanour violations are punishable by fines or imprisonment.