WASHINGTON – White House press secretary Sarah Sanders on Sunday called congressional Democrats' demands for copies of President Donald Trump's tax returns "a disgusting overreach" and warned they are headed down "a dangerous road."

"I don't think Congress, particularly not this group of congressmen and women, are smart enough to look through the thousands of pages that I would assume that President Trump's taxes will be," Sanders said during an interview on "Fox News Sunday."

"My guess is most of them don't do their own taxes and I certainly don't trust them to look through the decades of success that the president has and determine anything."

She later specified in a tweet that "Democrats in Congress aren’t smart enough to understand the President’s tax returns."

Trump has refused calls to release his tax returns since he announced he was running for president in 2015. His refusal has prompted some critics to insinuate that he does not want to disclose them because he has something to hide.

A number of commentators on Twitter pointed out that at least 10 members of Congress are accountants. Others observed that they also probably would hire experts to give the returns a thorough analysis.

Trump often claims he can't share his returns because he is under audit.

"The president has been clear from the beginning, as long as his taxes are under audit, he's not going to release them," Sanders said.

But IRS officials say an audit would not prevent someone from making their tax returns public.

House Ways and Means Committee Chairman Richard Neal, D-Mass., asked the IRS to hand over six years of Trump’s tax returns, citing a law that says the Treasury Department "shall furnish" the committee with "any return or return information" upon request. Trump's attorneys argued the release requires "legitimate legislative purpose."

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On Sunday, Sanders claimed that Congress can only ask for someone's tax returns "for the purpose of determining policy."

After Treasury Department Secretary Steven Mnuchin told Neal he would not be able to review his request in time to meet the initial deadline of April 10, Neal wrote a letter to IRS Commissioner Charles Rettig setting a new deadline of 5 p.m. April 23.

"If you fail to comply, your failure will be interpreted as a denial of my request," Neal said.

Neal said the law is "unambiguous and raises no complicated legal issues" and "it is not the proper function of the IRS, Treasury, or Justice to question or second guess the motivations of the Committee."

"Concerns about what the Committee may do with the tax returns and return information are baseless," he said.

Rep. Ted Lieu, D-Calif., tweeted that Trump should go ahead and hand over his returns.

"If we are not smart enough to understand them, we will send them back. Pinky promise," he said.

Most of the top candidates in the 2020 Democratic field have released their tax returns –or have said they plan to – and have been highly critical of what they say is the president's lack of transparency. Vermont Sen. Bernie Sanders said he will release a decade's worth of returns Monday.

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