Former President Donald Trump showed up on Monday for a trial in a lawsuit that could cost him control of Trump Tower and other prized properties, after vowing to defend his reputation in a case he calls "a sham."

Trump, who built his political career on his fame as a billionaire real estate ace and master of "The Art of the Deal," appeared voluntarily for a trial that has high stakes for him.

New York Attorney General Letitia James' suit accuses Trump and his company of deceiving banks, insurers and others by habitually lying about his wealth in financial statements.

Judge Arthur Engoron already has ruled that Trump committed fraud in his business dealings. It is a non-jury trial, so Engoron will decide on six other claims in the lawsuit.

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James, a Democrat, is seeking $250 million in penalties and a ban on Trump doing business in New York. The judge's ruling last week, if upheld on appeal, could force Trump to give up New York properties including Trump Tower, a Wall Street office building, golf courses and a suburban estate.

Trump, the Republican front-runner in the 2024 presidential race, has denied wrongdoing. He says that James and the judge are undervaluing such assets as Mar-a-Lago, and that it didn't matter what he put on his financial statements because they have a disclaimer that says they shouldn't be trusted.

In posts overnight on his Truth Social site, he said he was going to court "to fight for my name and reputation," denounced the case as "A SHAM," and called on the attorney general and judge to resign.

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Before the trial Monday, James reiterated her position that Trump for years engaged in "persistent and repeated fraud."

"No matter how powerful you are, and no matter how much money you think you have, no one is above the law," she said on her way into the courthouse.

The Republican former president and a who's who of people in his orbit — his two eldest sons, Trump Organization executives and former lawyer-turned-foe Michael Cohen are all listed among dozens of potential witnesses.

Trump isn't expected to testify for several weeks. His trip to court Monday will mark a remarkable departure from his past practice.

Trump didn't go to court as either a witness or a spectator when his company and one of its top executives was convicted of tax fraud last year. He didn't show, either, for a trial earlier this year in which a jury found him liable for sexually assaulting the writer E. Jean Carroll in a department store dressing room.

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In some ways, though, this new trial comes with higher stakes.

James, a Democrat, is seeking $250 million in penalties and a ban on doing business in New York.

Engoron's ruling of last week, if upheld on appeal, would also shift control of some of his companies to a court-appointed receiver and could force him to give up prized New York properties such as Trump Tower, a Wall Street office building, golf courses and a suburban estate.

Trump called it a "a corporate death penalty."

"I have a Deranged, Trump Hating Judge, who RAILROADED this FAKE CASE through a NYS Court at a speed never before seen," Trump wrote on his Truth Social platform.

In his post Sunday night, Trump wrote that Engoron is "unfair, unhinged, and vicious in his PURSUIT of me."

Engoron will decide on six remaining claims in James' lawsuit, including allegations of conspiracy, falsifying business records and insurance fraud.

James' lawsuit accused Trump and his company of a long list of falsehoods in the financial statements he gave to banks. In a recent court filing, James' office alleged Trump exaggerated his wealth by as much as $3.6 billion.

Among the allegations were that Trump claimed his Trump Tower apartment in Manhattan — a three-story penthouse replete with gold-plated fixtures — was nearly three times its actual size and worth an astounding $327 million. No apartment in New York City has ever sold for close to that amount, James said.

Trump valued Mar-a-Lago as high as $739 million — more than 10 times a more reasonable estimate of its worth, James claimed. Trump's figure for the Palm Beach, Florida, private club was based on the idea that the property could be developed for residential use. While Trump lives there, deed terms prohibit further residential development on the property, James said.

Trump has denied wrongdoing, arguing in sworn testimony for the case that it didn't matter what he put on his financial statements because they have a disclaimer that says they shouldn't be trusted.

He and his lawyers have also argued that no one was harmed by anything in the financial statements. Banks he borrowed money from were fully repaid. Business partners made money. And Trump's own company flourished.

James' lawsuit is one of several legal headaches for Trump as he campaigns for a return to the White House in next year's election. He has been indicted four times since March, accused of plotting to overturn his 2020 election loss, hoarding classified documents and falsifying business records related to hush money paid on his behalf.

The trial could last into December, Engoron said.