Shawn Thew – Pool/Getty Images(WASHINGTON) — House Democrats are expected to question Treasury Secretary Steven Mnuchin on Thursday about how he would handle a request from Congress for the president’s tax returns when he appears on Capitol Hill for a budget hearing.

Democrats, led by the Ways and Means Committee and Chairman Richard Neal, D-Mass., are carefully preparing to request 10 years of the president’s personal returns — and fight the subsequent legal battle expected — in the coming weeks.

“It would be completely legitimate to ask him about any topic that falls under his purview as secretary of the Treasury,” Rep. Brendan Boyle, D-Penn., a member of the panel, told ABC News. “It is actually a basic function of oversight that’s one of the main responsibilities of Congress.” The Treasury secretary is required to “furnish” any individual’s tax return information to the chairs of three congressional committees “upon written request,” under a 1924 provision of the federal tax code.

But the Trump administration is expected to fight the request, and a spokesperson for Mnuchin has told ABC News that the secretary would “review any request with Treasury’s attorneys for legality.”

“I’d be surprised if they didn’t [come up],” Rep. Bill Pascrell, D-N.J., a member of the committee who has pushed Democratic leaders to move quickly to request the returns, told ABC News.

Lawmakers have no shortage of other questions for Mnuchin, who will also appear before the Senate Finance Committee Thursday to discuss the president’s 2020 budget request.

Sen. Ron Wyden, D-Ore., the top Democrat on the panel, has raised questions about Treasury’s decision to ease sanctions on companies linked to Oleg Deripaska, a Russian oligarch with ties to the Kremlin.

Democrats also want to press Mnuchin on the impact of the GOP tax bill, including tax refunds. They previously sought his testimony on the partial government shutdown’s impact on taxpayers.

Copyright © 2019, ABC Radio. All rights reserved.