Treasury Secretary Steven Mnuchin said he did not know if Treasury’s legal department was reviewing whether he or IRS Commissioner Charles Rettig should be the one to make the decision on whether to hand over President Donald Trump’s tax returns to House Ways and Means Committee Chairman Richard E. Neal.

Mnuchin was quizzed about his reaction to Neal’s April 3 letter requesting six years of the president’s tax returns at a hearing Tuesday of the House Appropriations Financial Services subcommittee by the panel’s chairman Mike Quigley, an Illinois Democrat.

[Ways and Means chairman asks for Trump’s tax returns]

Quigley maintained, as former Treasury Secretary Lawrence Summers did in an opinion piece Monday that ever since a 1982 order, the Treasury Secretary has delegated tax administration and enforcement to the IRS commissioner and that would include the decision on the president’s tax returns.

“I want to acknowledged that we did receive the request and as I’ve said in the past …it would be reviewed by our legal department,” Mnuchin said. “It would be premature for me to comment on what they are reviewing on.”

While the IRS is under the Treasury Department, Neal’s request referencing his right to do so under Section 6103 of the tax code was directed to Rettig and a letter from Trump’s attorney in the matter, William Consovoy, was directed to IRS general counsel Brent McIntosh. Treasury Order 150-10 delegates “administration and enforcement of the Internal Revenue laws” to the IRS commissioner.

[Trump: ‘I Don’t Care’ if House Democrats Release My Tax Returns]

The “long-standing delegation order that the Secretary doesn’t get involved (in tax matters)…is not a delegation that’s easily revocable,” Quigley said referring to a requirement that the delegation order can only be rescinded after a 30-day notice to congressional committees, including Ways and Means and the Senate Finance Committee.

Mnuchin was also asked if he had communicated with either Trump or White House Acting Chief of Staff Mick Mulvaney about Neal’s request. He said he had not. Both Trump and Mulvaney have said the returns would not be provided to Neal, which would likely spur a lengthy court fight.

The only communication Mnuchin said he is aware of between any Treasury officials and any White House officials on the issue is “our legal department has had conversations prior to receiving the letter with the White House general counsel.” It “wasn’t exactly a state secret” that Neal was expected to make the request, he noted.

The powers given the tax-writing committee chairmen stems from a 1924 law that had its origin in conflict of interest and bribery allegations against administration figures and those the administration did business with at the time.

Section 6103 of the tax code appears straightforward: “Upon written request from the chairman of the Committee on Ways and Means of the House of Representatives, the chairman of the Committee on Finance of the Senate, or the chairman of the Joint Committee on Taxation, the Secretary shall furnish such committee with any return or return information specified in such request…”

According to a Congressional Research Service analysis there appears to be “no substantive limitations” on Neal’s right to obtain the returns. But the provision “arguably is subject to the same legal limitations that generally attach to Congress’ use of other compulsory investigative tools;” that is, the inquiry must further a “legislative purpose,” the analysis adds.

A legislative and oversight rationale was stressed in Neal’s letter seeking the returns and House Ways and Means even held a hearing in February on the history of presidential tax returns and Congress’ role in making sure the IRS, which is under presidential authority, fairly audits the president’s tax returns.

In his letter, Neal gave the IRS until April 10 to hand over six years of tax returns from the president and related companies.

“Consistent with its authority, the committee is considering legislative proposals and conducting oversight related to our Federal tax laws, including, but not limited to, the extent to which the IRS audits and enforces the Federal tax laws against a President,” Neal wrote in his April 3 letter. The IRS audits the returns of the president and the vice president every year.

Last Friday, Consovoy wrote to McIntosh, claiming Neal’s request for the president’s tax return was unsupported by law.

[Steven Mnuchin makes case to GOP to allow easing of sanctions on Russian companies]

He noted that “requests for tax returns and return information must have a legitimate legislative purpose. All legislative investigations ‘must be related to, and in furtherance of, a legitimate task of Congress.’”

“Even if Ways and Means had a legitimate committee purpose for requesting the

President’s tax returns and return information, that purpose is not driving Chairman Neal’s request,” Consovoy claimed. “His request is a transparent effort by one political party to harass an official from the other party because they dislike his politics and speech.”

On Monday, Summers, who was President Bill Clinton’s Treasury Secretary, in an opinion piece, pointed out that the statute allowing the IRS to provide tax returns to others, including the tax-writing committee chairman, has been applied many times before. Most recently, he noted, was when Republicans sought, obtained and released in 2015 tax information about taxpayers allegedly targeted by the IRS for their conservative ideologies.

Summers wrote that the decision should rest with the IRS commissioner and advised that Mnuchin not interfere with the decision-making process.

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