By AARON KATERSKY, ABC News

(NEW YORK) — A judge in New York on Tuesday rejected President Donald Trump’s claim of attorney-client privilege that could have shielded documents from the New York Attorney General’s office.

The Trump Organization was given until Friday to turn over documents from the engineer of its Seven Springs Estate, a property in Westchester County being investigated by Attorney General Tish James over how it was valued by the organization while seeking tax 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. James’ office is looking into whether an improper valuation let the Trump Organization take a $21 million tax deduction.

The Trump Organization had argued the engineer’s documents were privileged because they helped lawyers value the property, but Judge Arthur Engoron ruled that none of those documents met the standard of confidentiality.

“By December 18, 2020, the Trump Org. must produce all communications with Ralph Mastromonaco to the New York Attorney General’s office,” Engoron said.

Seven Springs is one of four Trump Organization properties that claimed New York state tax deductions and is part of an investigation that will follow the president once he leaves office.

The company had been asserting privilege over documents involving Mastromonaco, an engineer involved in the property’s 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 initially 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.

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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