An attorney for Donald Trump's adult sons, Eric Trump and Donald Trump Jr., added a brief opening statement of his own, defending his clients from accusations of wrongdoing.

"There was never a material misrepresentation made by Eric Trump or Donald Trump Jr.," said Clifford Robert, the attorney for Trump's adult sons, who help run the Trump Organization.

Robert said he disagrees "with just about everything" the state's prosecutor said in his opening remarks, and took aim at the state's star witness.

"Their major linchpin is Michael Cohen, a guy who lies to everyone," Robert said of the former Trump attorney.

Attorney General Letitia James "is setting a very dangerous precedent for any business in the state of New York," warned Trump attorney Alina Habba in her opening statement.

Habba told the court she hadn't planned to make opening remarks, but that she felt moved to speak after hearing the state present its own opening statement. Habba accused the attorney general of targeting Trump before taking office, claiming the investigation and lawsuit were personal in nature.

"We are attacking a sitting president and two of his children and his employees for a statement of financial condition which is frankly worth less than what they are worth," Habba said.

Habba reiterated many of the points made earlier by co-counsel Christopher Kise, highlighting the fact that "these lenders made money," and arguing that "real estate is malleable -- the values change."

After Habba concluded her remarks, Judge Engeron engaged her in a series of follow-up questions, asking about her claim that the property appraisals at issue were "undervalued" by prosecutors.

Habba replied that "the Trump brand is worth something."

Former President Trump's defense counsel will present a "very different picture of the evidence" than the prosecution alleges, and will demonstrate that "there are many ways to value assets," according to opening remarks from Christopher Kise, Trump's lead attorney.

"We think the evidence is going to establish … President Trump has made billions of dollars building one of the most successful real estate empires in the world," Kise said, reiterating sentiments he conveyed in pretrial motions.

Kise offered a glimpse into the former president's defense, including plans to present testimony from a New York University professor who will explain that "there is no one generally accepted procedure to determine the estimated current value" of a property.

Other defense witnesses, including four Deutsche Bank officers who were involved in approving Trump's loans, will explain how they were able to craft their own independent risk analyses meant to mitigate the claims of fraud that are core to the state's case.

"Anyone committing fraud does not tell the other side, 'Please do your own analysis,'" Kise said regarding Trump's instructions to lenders.

Kise also previewed plans to undermine the state's key witness, former Trump attorney Michael Cohen, who Kise said has "lied to everyone and anyone he has come in contact with."

Kise reiterated the defense's claim that Trump did not commit fraud and that there were no victims of his alleged conduct.

"The attorney general has no case," Kise said.

Prosecutors intend to prove in the coming months that "each defendant engaged in repeated, persistent, illegal acts in conduct of business," according to the opening statement from Kevin Wallace of the attorney general's office.

Referring to Judge Engoron's partial summary judgment last week, Wallace said that "the people have already proven" that former President Trump used "false, misleading" statements that were "repeatedly [and] persistently used in the conduct of business."

But prosecutors will further demonstrate that Trump and his co-defendants knew those statements were false and continued to peddle them anyway in furtherance of their alleged scheme, Wallace told the judge.

"The defendants were lying year after year," he said.

Wallace played clips of video depositions to punctuate his remarks, including testimony from Trump himself, as well as Eric Trump and former Trump attorney Michael Cohen -- whose congressional testimony years ago precipitated the state's investigation and some of the key allegations underpinning their case.

"The goal was to use each of [Trump's] assets and increase its value in order to get to the end result number," Cohen said during his taped deposition. "It was essentially backing in numbers to each of the asset classes in order to attain the number that President Trump wanted."

Trump and his co-defendants "knew that a high net worth was necessary to get and maintain certain financial benefits," Wallace said, pointing to basic principles of accounting and finance.

Throughout Wallace's remarks, the attorney general's office flashed graphics on television screens inside the courtroom showing some of the alleged inflated values of Trump's properties alongside the amounts the properties were appraised at.

Seated in his chair with his arms crossed, Trump visibly shook his head at times during the prosecutor's opening statement. At one point he seemed to mutter something under his breath.

The former president whispered with his attorneys throughout.

Testifying for the defense, former President Trump's eldest son described his father as a real estate "visionary" who "sees the sexiness in a real estate project," creating value for the family business that cannot be captured on paper.

Donald Trump Jr. began his testimony with a quip after Judge Engoron welcomed him back to the stand following his testimony earlier in the month.

"I'd say it's good to be here, but the attorney general would probably sue me for perjury," Trump Jr. joked.

In his testimony, Trump Jr. described the Trump Organization as "a large family business," with Trump and his eldest children at the top and other executives handling many of the details.

"If there were numbers and things, I would rely on them to give me that," Trump Jr. said.

He recounted the history of the Trump Organization, beginning with his great-grandfather who he said built hotels in the Yukon Territories of Canada. His grandfather, Fred Trump, "started working on job sites around Queens, learned the trades" and eventually "created an incredible portfolio, by the time of his passing, of rental apartments in Brooklyn and Queens."

A state attorney jokingly objected that references to the 1800s were outside the statute of limitations -- then more seriously objected to the history lesson's relevance.

"I think it is relevant to get the historical perspective -- I find it interesting," Judge Engoron said in overruling the objection. "Let him go ahead and say how great the Trump Organization is."

Trump Jr. obliged.

"My father learned a lot of the business from him, but had some flair and saw New York City and Manhattan as the ultimate frontier," he said. Speaking of Trump Tower, he said, "I think it would have been one of the first, I think great, ultra-luxury real estate emerging in Manhattan."