President Donald Trump always ignores the rules -- it's the secret of his political success.
Now, his habit of a lifetime is putting the checks and balances system of government to its gravest test in years as lawmakers return to Washington amid an escalating showdown over accountability.
Trump is adopting a strategy of all out resistance to sweeping Democratic efforts to use their House majority to investigate his conduct and his administration in a way that critics charge shows contempt for Congress and its constitutional role.
His gambit will force Democratic leaders to find new political and legal ways to compel cooperation as they seek to probe Robert Mueller's revelations, get Trump's tax returns, investigate his company, and force current and former administration officials to testify.
The highlight of a week of confrontation will be planned testimony in the Senate and the House on Wednesday and Thursday from Attorney General William Barr who has outraged Democrats by presenting the special counsel's report in a way that offered maximum political advantage to the President.
Lawmakers have been on recess since the release of a redacted version of the Mueller report earlier this month, sparing Republicans from being forced to weigh in on its picture of lying and chicanery, though apparently no crimes in the Trump White House.
That will change this week and GOP lawmakers are sure to point out when they are ambushed by reporters that Mueller did not establish a conspiracy between Trump's 2016 campaign and Russia and was unable to come to a conclusion on whether the President obstructed justice.
Amid the escalating war of oversight, House Speaker Nancy Pelosi and Democratic Senate minority leader Chuck Schumer will actually go to see Trump on Tuesday to try to find a way to work together -- on infrastructure.
The atmosphere of confrontation between the White House and Democrats on Capitol Hill however might make hopes of common ground, albeit in one area, elusive.
Barr tries to make the rules
The extent of that mistrust was evident in skirmishes over the weekend between the Justice Department and Democrats on Capitol Hill. Barr challenged the Democratic-led House Judiciary Committee over the terms of their hearing, putting his appearance in doubt.
In a statement issued on Sunday, the Department effectively said Barr would show up only if members of Congress ask the questions.
"The attorney general agreed to appear before Congress. Therefore, Members of Congress should be the ones doing the questioning," the statement said. "He remains happy to engage with Members on their questions regarding the Mueller report."
But Democratic Judiciary Committee chairman Jerrold Nadler told CNN Sunday that "the witness is not going to tell the committee how to conduct its hearing, period,"
Nadler plans to allow members to ask questions but also to use House Judiciary Committee counsels -- one from each party -- to follow up with questions.
Asked what he would do if Barr doesn't comply, Nadler, a New York Democrat, said: "Then we will have to subpoena him, and we will have to use whatever means we can to enforce the subpoena."
Trump's White House is already telling current and former officials to ignore other subpoenas.
His political counselor Kellyanne Conway hinted to CNN's Jake Tapper on "State of the Union" on Sunday that Trump would try to stop his former White House counsel Don McGahn from testifying about the Mueller report, including Mueller's evidence that the President told him to fire the special counsel.
"Executive privilege is always an option, it's always on the table. But Don McGahn has already talked under oath for 30 hours. And this is just presidential harassment," Conway said, adding that it's Trump's "right" to use such power.
In a separate showdown, Trump and his company last week launched a legal fight to stop his accountants from releasing his past financial statements to the House Oversight Committee.
Last week, the White House told former official Carl Kline not to comply after he was subpoenaed by the Oversight panel in an investigation over the administration's handling of security clearances.
The Treasury Department has meanwhile blown past two deadlines to hand over his tax returns to comply with a law that says three top congressional officials can see them if they have a legislative purpose.
The White House has also refused to make Trump's senior adviser Stephen Miller available for testimony about his role in immigration policy, citing a custom that top White House aides are not hauled before Congress.
Democrats look for a strategy
The administration's multi-front resistance to scrutiny is leaving Democratic leaders considering extraordinary measures to respond, including the opening of legal cases to enforce subpoenas and even threats to fine or jail targets that defy them.
A long legal confrontation that could spend months working its way through the courts is now all but inevitable. Some cases could eventually end up before the newly reconstituted conservative majority on the Supreme Court.
Trump, with his talent for shaping the political battle, is brandishing the narrative set by Barr over the Mueller report -- which ignores many of the special counsel's most troubling findings -- to put Democrats on the defensive.
"We finished no collusion, no obstruction right? Then I get out the first day they're saying 'Let's do it again,' and I said 'That's enough, we have to run a country," Trump told reporters on Friday.
"This is a pure political witch hunt ... if I'm guilty of anything, it's that I've been a great President and the Democrats don't like it, which is a shame."
Trump is more than happy to have the fight since he constantly looks for ways to energize his political base -- a factor that is even more important given the accelerating 2020 campaign.
And he is always happiest and often most effective in the middle of a fight in which his willingness to ignore conventions and the normal order of constitutional battle gives him a edge.
While the Democratic party is split over the issue of impeachment, there is agreement on the need to use the party's House majority to present a case to voters that Trump is so contemptuous of efforts to limit his power and that his administration is so corrupt that he is not fit to serve a second term.
"I think Mr. Mueller laid out for us a roadmap," said South Carolina Rep. James Clyburn on ABC News "This Week."
"There's one thing to run down a road toward impeachment. It's something else to lay a foundation, gather the facts, educate the American people so that we can see exactly what needs to be done and when we should do it," said Clyburn.
CNN's Manu Raju, Jeremy Herb, Laura Jarrett, Ted Barrett and Sara Murray contributed to this report.