By AARON KATERSKY, ABC News

(NEW YORK) — Donald Trump’s namesake company is invoking attorney-client privilege in an attempt to shield certain documents from the New York Attorney General’s office, which is conducting an investigation that will follow the president once he leaves office.

The attorney general’s office is looking into whether the Trump Organization improperly inflated the value of its Seven Springs Estate in Westchester County to claim a $21 million tax deduction.

The company is asserting privilege over documents involving Ralph Mastromonaco, an engineer involved in the appraisal.

“There is no accountant-client privilege, and there is no engineer-developer privilege,” Eric Haren, of the attorney general’s office, said Tuesday during oral arguments.

Haren claimed the Trump Organization effectively waived privilege over the property’s appraisal when the company submitted it to the IRS, though the judge questioned the argument.

“Is that your position? If you give the IRS a request for a deduction that anything that had to do with it is waived?” Judge Arthur Engoron asked.

“At no time did we waive any privilege assertions,” said Amy Carlin, an attorney for the Trump Organization.

She also argued Mastromonaco was performing a function covered by privilege doctrine.

“The fact that Mastromonaco was initially retained to provide certain specific engineering work doesn’t mean that he wasn’t also ultimately performing a Kovel function,” Carlin said, referring to a legal principle that extends attorney-client privilege to other sources of expert advice.

“What is the evidence that Mastromonaco was acting as an expert to explain things?” Engoron asked.

Seven Springs Estate is one of four properties Attorney General Tish James is investigating over the way the Trump Organization valued them while seeking tax and other benefits from New York state.

At issue is whether the property’s conservation easement is legitimate. The president’s son, Eric, sat for a deposition.

The investigation stems from the congressional testimony of Michael Cohen, the president’s former fixer and attorney, who has pleaded guilty to lying and campaign finance violations.

“It was my experience that Mr. Trump inflated his total assets when it served his purposes, such as trying to be listed amongst the wealthiest people in Forbes, and deflated his assets to reduce his real estate taxes,” Cohen said in February 2019.

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