Letitia James has since March 2019 been looking into the tax affairs of the Trump Organization after former Trump confidante Michael Cohen talked about its businesses.
James is looking at whether the Trump Organization increased the value of its assets to claim tax relief.
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James said that the former President claimed his Trump Tower penthouse was 30,000 square feet and worth $327 million, when in fact it was 11,000 square feet and worth a bit of that.
He also inflated the value of his golf course in Scotland and falsely stated that members of his Westchester club were paying $150,000 to join.
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The Trumps misrepresented the value to banks, insurance companies, and the IRS, James said.
"We are taking legal action to force Donald Trump, Donald Trump, Jr., and Ivanka Trump to comply with our investigation into the Trump Organization's financial dealings," said James.
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"No one in this country can pick and choose if and how the law applies to them.
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"We have uncovered significant evidence indicating that the Trump Organization used fraudulent and misleading asset valuations on multiple properties to obtain economic benefits, including loans, insurance coverage, and tax deductions for years."
James said that Trump and his son Don Jr, 44, and daughter Ivanka, 40, were acting mysteriously and inappropriately.
"Donald Trump, Donald Trump, Jr., and Ivanka Trump have all been closely involved in the transactions in question, so we won't tolerate their attempts to evade testifying in this investigation.
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"We will not be deterred in our efforts to continue this investigation, uncover the facts, and pursue justice, no matter how many roadblocks Mr. Trump and his family throw in our way."
The court filing said state authorities have not yet determined whether to bring a civil lawsuit in relation to the claims, but that investigators need to challenge Trump and his two eldest children as part of the investigation.
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Trump and his lawyers say the probe is politically driven.
In the court data, James' office gave its most detailed accounting yet of its probe into allegations that Trump's company repeatedly distorted the value of assets to get favorable loan terms or slash its tax burden.
It said that the Trump Organization had exaggerated the value of land donations made in New York and California on paperwork presented to the IRS to justify several million dollars in tax deductions.