Democrats don’t expect Treasury Secretary Mnuchin or IRS Commissioner Rettig to comply.

Rep. Richard Neal issued subpoenas Friday to the Treasury secretary and IRS chief seeking six years of President Trump’s tax returns and audit records, taking the next formal step in the dispute between House Democrats and the Treasury Department. Democrats don’t expect Treasury Secretary Steven Mnuchin or Charles Rettig, commissioner of the Internal Revenue Service, to comply with the subpoenas, following Mr. Mnuchin’s rejection of a previous written request from Mr. Neal and following the administration’s general refusal to provide documents for House Democrats’ investigations. The subpoenas, issued on the advice of House lawyers, link the tax-return fight to the existing body of law governing congressional information requests.

Mr. Neal, a Massachusetts Democrat, requested the tax records last month, using a power the tax code gives him as chairman of the Ways and Means Committee. Under that provision, which dates to the aftermath of the Teapot Dome scandal in 1924, the chairman can seek any taxpayer’s returns and the Treasury secretary “shall furnish” them. The law is clear, but Mr. Mnuchin argued in a letter on Monday that Mr. Neal’s request exceeded Congress’s constitutional authority because it lacked a legitimate legislative purpose. Mr. Mnuchin wrote that the Justice Department would publish a more detailed legal opinion, though that hasn’t happened yet.

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