An accountant who worked on the tax returns of testified Monday as the first witness at the former president's $250 million civil in .
The accountant, former Mazars USA partner Donald Bender, estimated that from 2011 until his retirement he spent an estimated 45% to 55% of his work time on Trump-related work.
"I worked on his tax returns, tax exams," Bender told Kevin Wallace, a lawyer in the office of New York Attorney General Letitia James.
The accountant also testified he did work on corporate entities controlled by Trump and his children.
Trump, who was seated in the courtroom, appeared agitated at Bender's testimony toward the end of the day, NBC News reported. His face at times turned red, and at one point he pointed and waved his finger around while whispering aggressively to a defense attorney.
Bender took the stand after a tense first half of the day, in which an attorney for Trump clashed with the judge, and the former president stared down James, whose lawsuit is the subject of the trial.
The attorney, Christopher Kise, at one point stood and admonished Manhattan Supreme Court Judge Arthur Engoron.
"You owe it to the defendant to listen to the evidence," Kise said.
Kise also complained about a person included on the list of potential witnesses submitted by .
During the exchange, Trump shook his head, shifted in his seat and turned toward the gallery, NBC reported.
On his way out of the courtroom for a lunch break, Trump shot an angry glare at James, who was seated behind him.
The trial comes a year after sued him, his , three of his adult children, and top officials.
James alleged the defendants misstated the values of properties by billions of dollars in business records to obtain better loan and insurance terms, and tax benefits.
Her suit seeks to bar Trump and other defendants from ever running a business in New York again.
Before Monday's trial began, Trump claimed the case was a "witch hunt" aimed at undermining his campaign for the 2024 GOP presidential nomination.
"Everything was perfect. There was no crime. The crime is against me," Trump told reporters in the courthouse hallway.
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James notched a massive win against Trump and other defendants last week when Engoron ruled they were liable for the fraud claims. Engoron in that ruling canceled the defendants' New York business certificates and ordered an independent receiver to oversee their dissolution.
Engoron, not a jury, will decide whether the defendants are liable for the other six claims at the trial, which is expected to conclude in late December.
"The people have already proven" that Trump's financial statements from 2011 to 2021 were "false and misleading," said Wallace, the AG's lawyer, in his opening statement to the judge.
Wallace played video clips of depositions from key witnesses, including Trump, former Trump Organization Chief Financial Officer Allen Weisselberg and Trump's former personal attorney Michael Cohen.
In one clip, Cohen said that he and Weisselberg would inflate the value of real estate assets to reach the figure that Trump wanted in order to help him climb higher on Forbes' wealth rankings.
Wallace argued that while a person may exaggerate their wealth for Forbes magazine or for television audiences, they "cannot do it while conducting business in the state of New York."
But Trump's lawyer Kise said the evidence will show that "there was no intent to defraud."
The loans that Trump's business secured were "successful" and "profitable," Kise said.
"The banks made well over a hundred million dollars," Kise added.
James, in a statement shortly before the trial began, said, "For years, Donald Trump falsely inflated his net worth to enrich himself and cheat the system."
"We won the foundation of our case last week and proved that his purported net worth has long been rooted in incredible fraud," James said. "No matter how rich or powerful you are, there are not two sets of laws for people in this country. The rule of law must apply equally to everyone, and it is my responsibility to make sure that it does."
Ivanka Trump was removed from the case in June, after an appeals court ruled that the claims against her were barred by the statute of limitations. But two of Trump's other children, Donald Trump Jr. and Eric Trump, who took over the family business after their father became president in 2016, remain as defendants.