Suing Deutsche Bank. Threatening the IRS commissioner. Ordering subordinates to ignore congressional subpoenas.

The last few weeks have seen the Trump White House and President Trump personally open up new, dramatic fronts in his war on congressional oversight.

Conflict between branches of government — especially when they are controlled by opposing parties — is nothing new. Few observers expected the Trump administration to roll over and provide Democrats with volumes of documents and evidence once they took control of the House.

But this stonewalling represents a never-before-seen pattern of thwarting Congress’ right to monitor the executive, former congressional staffers and historians told TPM. The country is witnessing a breakdown in the incentives that have traditionally driven oversight in American politics, they said.

The intensity of the fight has shocked many.

“In my 40 years of experience, since I started work for the Congress in 1979, I have never seen this level of resistance and refusal,” former House solicitor and deputy general counsel Charles Tiefer, now with of the University of Baltimore Law School, told TPM.

Former Historian of the House of Representatives Raymond W. Smock agreed that te current situation is “unprecedented.”

“Even during Watergate, you had Nixon’s people coming up and testifying and providing documents,” Smock told TPM. “There was pushback, but they came.”

The congressional investigations encompass Trump’s finances and the Trump Organization’s alleged tax violations. Lawmakers are looking into whether Trump is actually being audited by the IRS, and whether he is violating the U.S. Constitution’s Emoluments clause — which prohibits elected officials from benefitting from foreign gifts — by continuing to control his businesses.

And those are just probes delving into Trump’s personal financial issues. Other investigations are reviewing if his administration overruled career government employees on issues from granting security clearances to members of Trump’s family, Homeland Security’s family-separation policy at the border, and the effect of the partial government shutdown.

Faced with this daunting slate of investigations, Trump is refusing to give a single inch. The President said last month that he is “fighting all the subpoenas,” and told the Washington Post that he opposed any of his aides testifying before Congress.

Former White House personnel director Carl Kline was facing a contempt of Congress citation for following Trump administration guidance to ignore a subpoena to testify about the security clearance issue, and a noisy back-and-forth is ongoing over whether Trump will assert executive privilege to prevent ex-White House counsel Don McGahn from testifying before Congress. The Justice Department has refused to release an unredacted copy of the Mueller report, with House Judiciary Committee chair Jerry Nadler (D-NY) currently threatening to hold Bill Barr in contempt over the issue.

Barr himself refused to appear before Nadler’s committee on Thursday, after Democrats on the panel voted to allow staff attorneys to pepper the attorney general with additional rounds of questions.

The House Ways and Means Committee’s request for Trump’s tax returns appears headed for lengthy litigation, after the Treasury Department suggested that the demand “threatens the privacy of all taxpayers.”

In that case, Trump personal attorney William Consovoy has been sending his own letters to the IRS, threatening it with a lawsuit if it complies with House Democrats’ requests.

Trump is using Consovoy to stop investigations in other venues as well. The conservative movement lawyer has filed two suits — one against his accounting firm Mazars and one against Deutsche Bank — to stop financial institutions from complying with House subpoenas asking for information about the President’s finances.

Rather than laying out specific opposition to lawmakers’ demands, Trump and his representatives are arguing, outright, that Congress lacks the authority to conduct this type of robust oversight of the executive branch. Their legal arguments seek to protect him both in his private capacity as a businessman and his official capacity as commander-in-chief of the United States.

“‘Oversight’ and ‘transparency,’ in a vacuum, are not legitimate legislative purposes that can justify subpoenaing a private citizen,” Consovoy wrote in the Deutsche bank lawsuit.

Trump is also not the only challenger in that suit. His close family members and businesses are suing along with him, and all are represented by Consovoy.

“It’s hard to know whether this is a personal vendetta because he’s such a pugilist and his mantra is to fight everything tooth and nail, and to figure out where claims about executive privilege that fit more consistently begin,”said Jay Wyatt, director of the Byrd Center for Congressional History.

A court decision agreeing with Trump’s personal attorneys that Congress can only investigate the President in relation to specific legislation could seriously curtail the legislative branch’s oversight powers.

GOP lawmakers’ eager abetting of Trump’s stonewalling also indicates a deeper breakdown in constitutional norms and incentives, historians told TPM.

Traditionally, top White House and congressional officials were reluctant to engage in tactics that could fundamentally change the separation-of-powers playing field. Knowing that majorities in Congress shift and control of the White House changes hands, there was a clear incentive to maintain balance.

“That certainly does not seem to be [Sen.] Mitch McConnell (R-KY)’s way of governing,” Russell Riley, a presidential scholar at the University of Virginia’s nonpartisan Miller Center, told TPM. “That’s, ‘I will do whatever I can do right now and the future be damned.'”

McConnell seems to see it as part of a tradeoff in which the Senate gets to keep filling vacancies in the federal judiciary in exchange for letting the executive operate unchecked, according to Riley.

“It’s a payoff of immediate consequences in the judiciary paid for at the expense of the durability of the legislative branch of government,” Riley said.

It’s unclear whether Trump and his attorneys are actually counting on the arguments to succeed, or if they’re just a stalling tactic. But with only 18 months until the next presidential election, time is on the President’s side.

“President Trump’s lawyers would surely like a completely defeat of these House inquiries,” Tiefer, the former House attorney, said. “But if they delay them past election day 2020, they’ll consider themselves to be the winners.”