"One thing I know a lot about is the legal definition of fraud," Justice Arthur Engeron said as he gaveled court into session prior to the start of opening statements.

Engoron opened the proceedings after allowing cameras in to document the scene in the courtroom: Trump, arms folded, flanked by his legal team; Engeron on the bench; and throngs of reporters and spectators in the gallery.

"I've promised to do my best despite my lame attempts at humor," Engeron said in a brief opening statement. "I take my job very seriously."

The trial is expected to last through Dec. 22, Engeron said, and suggested he would attempt to keep a low profile after today.

"For the next three months, I hope the only words I will mutter are 'Sustained,' 'Overruled,' and 'Let's take a 10-minute break,'" he said.

Opening statements are underway in former President Trump's $250 million fraud trial.

Trump is seated between his attorneys Clifford Robert, Alina Habba and Christopher Kise.

Trump and his co-defendants face a bench trial, meaning that the sole arbiter of the case is Judge Arthur Engoron instead of a jury.

Former President Trump has taken a seat in the courtroom for the start of the trial.

"The crime is against me," he told reporters outside the courtroom before he made his way inside.

He denounced the case in now-familiar terms, criticizing state Attorney General Letitia James as she sat inside the courtroom.

Trump also accused Judge Arthur Engoron of failing to account for the full value of his real estate portfolio, asserting his Mar-a-Lago estate is worth "50 to 100 times more" than the judge's decision for partial summary judgment said last week.

"We have other properties, the same thing. So he devalued everything," Trump said. "We have among the greatest properties in the world. and I have to go through this for political reasons."

Engoron decided Trump's statements of financial condition were fraudulent, but Trump said, "We have a clause in the contract that says, essentially, buyer beware."

Former President Trump, speaking to reporters on his arrival at the lower Manhattan courthouse, said the trial is a witch hunt resulting from his standing in the presidential polls.

"This is a continuation of the greatest political witch hunt of all time," he told reporters outside the courtroom.

Trump said he is innocent of the accusations and that his portfolio has a much higher value than what the attorney general alleges.

After claiming a net worth of $8 billion, Donald Trump declined to share his financial statements with bankers related to his $1 billion bid to purchase the Buffalo Bills football team in 2014, according to documents presented at trial and testimony from Morgan Stanley executive K. Don Cornwell.

Of the 86 parties contacted to potentially bid on the Bills, Trump was one of six parties to make a final bid, according to a Morgan Stanley document shown at trial.

However, when Morgan Stanley attempted a close review of Trump's bid, Trump declined to provide his financial statements.

"We feel it is premature to sign the consent release forms until such time as we know that Mr. Trump is the final bidder," then-Trump attorney Michael Cohen said in a 2014 email shown at trial.

During a management presentation with Bills' leadership, Trump instead handed out a Forbes magazine list to support his bid, according to Cornwell.

"He gave us handouts of the Forbes list of the top-paid entertainers," Cornwell said.

Trump eventually lost his bid to purchase the football team to billionaire Terry Pegula, who outbid Trump by $400 million.

During cross-examination, Cornwell acknowledged that a lawsuit Trump previously brought against the NFL, as well as his affiliation with casinos, also limited the likelihood of his success.

"You thought that President Trump had little chance of being approved by the NFL?" defense attorney Ivan Feris asked.

"Yes," Cornwell replied.

Trump's lawyers have argued that his bid to purchase the Bills -- which has featured prominently in the testimony of other witnesses -- is irrelevant to the conduct alleged in the attorney general's lawsuit.

"It is the defense position that none of this relates to a cause of action in this case," Feris said.