President Trump railed about “PRESIDENTIAL HARASSMENT!” on Twitter Tuesday, but his anger did not deter Democratic lawmakers, who were poised to ask the Treasury Department for a decade of the commander-in-chief’s tax returns.

Congressional Democrats will fashion their request in a way they hope would survive a likely court battle, as Trump has vowed not to allow Treasury Secretary Steven Mnuchin to release his returns, the Washington Post reported.

Democrats led by House Ways and Means Committee Chairman Richard Neal of Massachusetts along with congressional lawyers were nearly finished drafting the request.

They are relying on a 1924 law that gives the chairs of the House and Senate tax-writing committees the power to demand the tax returns of White House officials.

Trump is the first president in decades to not make his returns public.

The White House has insisted that voters don’t care about the president’s taxes, and that the issue was settled in the 2016 election.

Although Trump has told pals there was no way he would let Mnuchin release the returns, the 1924 law does not appear to give the Treasury secretary much wiggle room, as the law says he “shall” turn over the records, the paper reported.

If he refuses, Democrats would likely try to force Mnuchin to play ball by suing in federal court, a case that could wind up before the Supreme Court.

“What the president will do is: He will, first of all, respond grudgingly and slowly. They will then negotiate,” former House Speaker Newt Gingrich told the paper.

“They will be subpoenaed. They will take that all the way to the Supreme Court.”

The quest for Trump’s tax returns is just the latest effort by House Democrats to scrutinize the president since they took back control of the chamber in the midterms.

The House Judiciary Committee on Monday launched a sweeping investigation into Team Trump, serving document requests on 81 government agencies, entities and individuals — including his two eldest sons, Don Jr. and Eric — as part of a probe into alleged obstruction of justice by the president.

Meanwhile, the chairmen of three House committees that are investigating the administration sent a letter to the White House seeking information about Trump’s conversations with Russian President Vladimir Putin.