Donald Trump Jr. testified on Monday about what he called the "sexiness" of his father's real estate portfolio, in his second time taking the stand in the former U.S. president's civil fraud trial.

Donald Trump, the frontrunner for the 2024 Republican presidential nomination, is accused along with his two adult sons and 10 of his companies of inflating his net worth by as much as $2.2 billion to secure better financing.

The lawsuit by New York Attorney General Letitia James seeks at least $250 million in damages as well as restrictions that would effectively bar Trump and his adult sons from New York's real estate industry.

In an apparent bid to show that the properties' high valuations were justified, defense lawyer Clifford Robert walked Donald Jr. through a lengthy slideshow of the Trump portfolio.

Donald Jr. said the "sexiness" of his father's real estate projects attracted licensing deals with other developers who wanted to emulate his style.

"He was really a visionary," he testified.

Lawyers' for James' office objected to the line of questioning as irrelevant, but Justice Arthur Engoron disagreed.

"Let him go ahead and talk about how great the Trump Organization is," said Engoron, who has defended himself during the trial from allegations of bias from Trump and his lawyers.

On cross examination, state lawyer Colleen Faherty showed Donald Jr. evidence that Trump's 40 Wall Street property in Manhattan is at risk of defaulting on its mortgage amid slumping occupancy rates, as well as a news article saying a Trump hotel in Hawaii is dropping a branding deal with his father.

Donald Jr. was the first witness called by the defense, which expects its case to last about a month.

He had already been called as a witness by the attorney general's office, along with his father and brother Eric Trump. His sister Ivanka Trump also testified but is not a defendant.

Trump has denied wrongdoing and accused James, an elected Democrat, of "election interference."

During defiant and rambling testimony last week, Trump acknowledged inaccuracies on his financial statements but said the discrepancies were not relevant to the banks that used them to price his loans.

Donald Jr., Eric and Ivanka Trump said they were not involved in preparing their father's financial statements and left bookkeeping at the Trump Organization to accountants.

The case is largely about damages, as Judge Engoron has already ruled that Trump and his company fraudulently inflated those asset values.

Engoron has ordered the dissolution of companies that control pillars of Trump's real estate portfolio, including Trump Tower in Manhattan. That ruling is on hold pending appeal.

Trump faces a maelstrom of legal troubles as he campaigns to challenge Democratic President Joe Biden in the 2024 election, though none have diminished his commanding lead over Republican rivals.

He is a defendant in four criminal trials, including two stemming from his attempts to overturn his 2020 election loss. He has pleaded not guilty in all four cases.