The People of the State of New York v. Donald J. Trump, et al, is scheduled to get underway in lower Manhattan at 10 a.m. with opening statements.

If opening statements are completed before the end of the day, the New York attorney general plans to begin her case by calling Trump's former Mazars USA accountant Donald Bender to the stand.

Mazars severed its business relationship with the former president last year after learning of the attorney general's findings during the AG's probe.

Though Trump has denied all wrongdoing alleged by the attorney general, Judge Arthur Engoron has already decided the central allegation against Trump and his co-defendants, ruling in a pretrial hearing last week that the AG had provided "conclusive evidence" that Trump overvalued his assets between $812 million and $2.2 billion.

The judge then canceled the Trump Organization's business certificates in New York, severely restricting Trump's ability to conduct business in the state moving forward -- a move that Trump attorney Alina Habba called "nonsensical" and "outrageously overreaching."

"In defendants' world: rent regulated apartments are worth the same as unregulated apartments; restricted land is worth the same as unrestricted land; restrictions can evaporate into thin air," Engoron wrote, citing multiple arguments made by defense to justify the allegedly inflated valuations of Trump's assets. "That is a fantasy world, not the real world."

Among the issues still to be determined at trial: What additional penalties Trump might face, and what might happen with the multiple causes of action included in the attorney general's suit.

Former President Donald Trump stepped up his attacks on the judge overseeing and deciding his case, writing on Truth Social overnight that Justice Arthur Engoron should resign and be sanctioned for "abuse of power."

Similar to an earlier post, Trump criticized allegations regarding the value of his Mar-a-Lago estate, in addition to an appellate court's ruling that his lawyers unsuccessfully tried to use to limit the timeframe of the case.

Former President Trump posted on his Truth Social platform Sunday night that he intends to attend the opening of the trial.

"See you in court -- Monday morning," he wrote in a post.

Earlier Sunday, multiple sources familiar with the decision told ABC News that Trump was expecting to attend.

Trump will have no speaking role in court on Monday, but it is anticipated that he'll return to the courthouse toward the end of the state's case when court records show he will be called as a witness.

State attorney Kevin Wallace is expected to complete his cross-examination of the defense's expert witness Robert Unell, who yesterday provided the most direct challenge to the state's analysis that found that Donald Trump's misstatements cost his lenders $168 million in lost interest.

New York Attorney General Letitia James is expected to use that lost interest analysis to justify part of the fine she wants to levy against Trump -- also known as a disgorgement -- for his allegedly ill-gotten gains.

Unell testified yesterday that he found the lost-interest analysis conducted by the state's expert Michiel McCarty was inaccurate based on real-world market conditions, including the interest rates used by commercial real estate lenders who are "living and breathing these deals daily."

"I have not seen anything to indicate that was an accurate interest rate," Unell said about the interest rates in the state's analysis.

Judge Arthur Engoron twice interjected during Unell's testimony to suggest that Trump still cost his lenders money, referring back to his partial summary judgment in which he said, "The less collateral for a loan, the riskier it is, and a first principal of loan accounting is that as risk rises, so do interest rates."