Washington — The top lawyer in the White House warned the leading Democrat on the House Oversight and Government Reform Committee that investigations into the Trump administration that lawmakers plan to pursue in the next Congress “may cross the line into blatant criminality” and said congressional subpoenas could prompt probes from the executive branch.

The message from White House counsel Will Scharf to Rep. Robert Garcia, a California Democrat who is set to chair the Oversight Committee as of January, foreshadows a brewing fight between the Trump administration and congressional Democrats, who are poised to launch investigations in a slew of issues arising over the first two years of Mr. Trump’s second term.

Scharf sent a letter to Garcia, dated Monday, reminding him that investigative acts by Congress must be backed by a “legitimate legislative purpose.”

“Beyond being inconsistent with the clear, well-recognized constitutional limitations on your investigative functions, threats to executive branch officials designed to deter them from public service, or process designed merely to abuse or instill fear in the recipient may cross the line into blatant criminality,” Scharf wrote. “And issuing unlawful subpoenas with the intention of depriving citizens of their constitutional rights and privileges may warrant further investigation.”

Scharf cited recent statements from Democratic members of Congress who previewed investigations into the Trump administration they plan to pursue once they take control of the House and Senate. He claimed that Democrats are intent on crossing the Constitution’s limits on congressional investigations and subpoenas.

“Abusive threats and public statements about the indiscriminate issuance of subpoenas, along with threats directed at prospective targets within the Administration make it abundantly clear that any forthcoming investigative processes will be deployed to harass and aggrandize rather than to advance any legitimate end,” he wrote. 

Scharf accused Democrats of making “abusive and capricious threats” and said they are seeking to “abuse the legislative process to intimidate and to interfere with lawful functioning of government.”

Garcia said in response to Scharf that the White House is threatening to infringe on his committee’s right to conduct oversight.

“It appears Donald Trump has something to hide,” the California Democrat said in a statement. “Let’s be clear: Congress’ authority comes from Article I of the Constitution, not from the permission of the White House. Congress has wide latitude to conduct investigations and oversight, an authority inherent in the power to legislate.”

Garcia accused the Trump administration of weaponizing the executive branch against Congress.

“We are a co-equal branch of government and will not be deterred by baseless threats from a weaponized DOJ or from the President’s lawyers,” he said.

Following last week’s midterm elections, Democrats are poised to hold at least 254 seats in the House and 54 seats in the Senate, giving them control of congressional committees and subpoena power.

Garcia had a brief message to the Trump administration on the heels of Democrats’ rout of Republicans in the fight for control of Congress: “Lawyer up.”

Once he takes the gavel of the Oversight Committee, the panel is expected to look into the Trump family’s business dealings, corporate corruption, actions by federal immigration authorities and the scandal involving convicted sex offender Jeffrey Epstein.

Garcia said his investigative agenda could also include:

• Donald Trump Jr.’s wedding festivities in the Bahamas that were partially paid for by a Russian oligarch.
• A $2 billion investment that the private equity fund of Mr. Trump’s son-in-law, Jared Kushner, received from Saudi Arabia’s sovereign wealth fund.
• The Trump family’s crypto ventures.
• Companies linked to the president’s sons that have received Pentagon contracts.
• Allegations of a pay-to-play scheme and other kickbacks related to Department of Homeland Security contracts.
• Corporate donations to fund the new White House ballroom.

Faced with investigations once Democrats regain congressional majorities, Mr. Trump on Sunday accused Democrats of threatening senior members of his administration and claimed they were engaging in “extortion.” The president said on Truth Social the Democrats “should be held accountable for this,” and he directed the Justice Department to look into their oversight push.

“These SLEAZEBAGS should go to jail for what they are doing,” he wrote in a second Truth Social post.

Democrats in Congress have in the past faced resistance from the White House in its efforts to investigate Mr. Trump and his administration. During the president’s first term, Democratic-led House committees sought a trove of Mr. Trump’s financial records from his accounting firm and two banks as part of an investigation into potential misconduct before and after he took office, whether he had undisclosed conflicts of interest and if he was complying with the Constitution.

Mr. Trump attempted to block the firms from complying with the subpoenas and took the dispute to the Supreme Court. In a 2020 decision, the high court declined to immediately give Congress access to the financial records, but reiterated that subpoenas must serve a “legitimate legislative purpose” and acknowledged that lawmakers have “significant legislative interests.”