WASHINGTON (AP) — President Donald Trump’s legal team asserted Monday that he did “absolutely nothing wrong,” urging the Senate to swiftly reject an impeachment case that it called “flimsy” and a “dangerous perversion of the Constitution.” The lawyers decried the impeachment process as rigged and insisted that abuse of power was not a crime.

The brief from Trump’s lawyers, filed before arguments expected this week in the Senate impeachment trial, offered the most detailed glimpse of the lines of defense they intend to use against Democratic efforts to convict the president and oust him from office over his dealings with Ukraine. It is meant as a counter to a filing two days ago from House Democrats that summarized weeks of testimony from more than a dozen witnesses in laying out the impeachment case.

The 110-page filing from the White House shifted the tone toward a more legal response. It still hinged on Trump’s assertion he did nothing wrong and did not commit a crime — even though impeachment does not depend on a material violation of law but rather on the more vague definition of “other high crimes and misdemeanors” as established in the Constitution.

“It is a constitutional travesty,” the lawyers wrote.

The document says the two articles of impeachment brought against the president — abuse of power and obstruction of Congress — don’t amount to impeachment offenses. It asserts that the impeachment inquiry, centered on Trump’s request that Ukraine’s president open an investigation into Democratic rival Joe Biden, was never about finding the truth.

“Instead, House Democrats were determined from the outset to find some way — any way — to corrupt the extraordinary power of impeachment for use as a political tool to overturn the result of the 2016 election and to interfere in the 2020 election,” Trump’s legal team wrote. “All of that is a dangerous perversion of the Constitution that the Senate should swiftly and roundly condemn.”

The prosecution team of House managers was expected to spend another day on Capitol Hill preparing for the trial, which will be under heavy security. Before the filing, House prosecutors arrived on Capitol Hill to tour the Senate chamber.

The impeachment case accuses Trump of abusing power by withholding military aid from Ukraine at the same time that the president was seeking an investigation into Biden, and of obstructing Congress by instructing administration officials not to appear for testimony or provide documents, defying congressional subpoenas.

In a brief filed Saturday, House Democrats called Trump’s conduct the “worst nightmare” of the framers of the Constitution.

“President Donald J. Trump used his official powers to pressure a foreign government to interfere in a United States election for his personal political gain,” the House prosecutors wrote, “and then attempted to cover up his scheme by obstructing Congress’s investigation into his misconduct.”

But Trump’s team contended Monday that even if Trump were to have abused his power in withholding the Ukraine military assistance, it would not be impeachable, because it did not violate a specific criminal statute. And it said that the White House was within its legal right to shield close advisers of the president from having to appear before Congress, saying that position has been taken by administrations of both parties.

Opening arguments are expected within days following a debate Tuesday over rules, including about whether witnesses are to be called in the trial.

Trump signaled his opposition to witnesses, tweeting Monday: “They didn’t want John Bolton and others in the House. They were in too much of a rush. Now they want them all in the Senate. Not supposed to be that way!”

That’s a reference to former national security adviser John Bolton, who was not subpoenaed by the House in its impeachment inquiry but has said he is willing to testify in the Senate if he is subpoenaed.

The White House brief argues that the articles of impeachment passed by the House are “structurally deficient” because they charge multiple acts, creating “a menu of options” as possible grounds for conviction.

The Trump team claims that the Constitution requires that senators agree “on the specific basis for conviction” and that there is no way to ensure that the senators agree on which acts are worthy of removal.

As part of their defense, Trump’s attorneys also mounted a broad defense of presidential power, arguing that the two other impeachment trials in the nation’s history were similarly defective.

The White House brief argues that the articles of impeachment passed by the House are “structurally deficient” because they charge multiple acts, creating “a menu of options” as possible grounds for conviction.

The Trump team claims that the Constitution requires that senators agree “on the specific basis for conviction” and that there is no way to ensure that the senators agree on which acts are worthy of removal, because a single count contains multiple allegations.

Administration officials have argued that similar imprecision applied to the perjury case in the impeachment trial of President Bill Clinton, who was acquitted by the Senate.

The Trump lawyers accused Democrats of diluting the standards for impeachment, an argument that echoed the case made Sunday by one of Trump’s attorneys, Alan Dershowitz, who contended in talk shows that impeachable offenses must be “criminal-like conduct.”

That assertion has been rejected by scholars, and Rep. Adam Schiff, the Democratic chairman of the House Intelligence Committee, called it an “absurdist position.”

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Trump’s lawyers on Sunday previewed their impeachment defense with the questionable assertion that the charges against him are invalid, adopting a position rejected by Democrats as “nonsense.”

The trial resumes on Tuesday with what could be a fight over the ground rules. By then, both sides will have submitted briefs and four Democratic presidential candidates will have been forced back to Washington from the early nominating states to join every other senator in silence, sans phones, on the Senate floor.

What they’re likely to hear in this extraordinary setting is the House Democrats’ impeachment articles that charge Trump with abuse of power and obstruction of Congress over his pressure on Ukraine for political help. From the White House, the senator-jurors are expected to hear that Trump committed no crime, the impeachment articles are invalid and he’s the victim of Democrats who want to overturn his election.

“Criminal-like conduct is required,” said Alan Dershowitz, a constitutional lawyer on Trump’s defense team. Dershowitz said he will be making the same argument to the Senate and if it prevails, there will be “no need” to pursue the witness testimony or documents that Democrats are demanding.

But the “no crime, no impeachment” approach has been roundly dismissed by scholars and Democrats, who were fresh off a trial brief that called Trump’s behavior the “worst nightmare” of the country’s founders. In their view, the standard of “high crimes and misdemeanors” is vague and open-ended in the Constitution and meant to encompass abuses of power that aren’t necessarily illegal.

The White House is pushing an “absurdist position,” said Rep. Adam Schiff, D-Calif., the lead Democratic prosecutor of the impeachment case. “That’s the argument I suppose you have to make if the facts are so dead set against you.” Rep. Jerrold Nadler, D-N.Y., another impeachment prosecutor, called it “arrant nonsense” and said evidence of Trump’s misconduct is overwhelming.

The back-and-forth came as all concerned agitated for the Senate to get on with the third impeachment trial in the nation’s history. Behind the scenes. the seven House managers were shoring up which prosecutor will handle which parts of the case and doing a walk-through of the Senate. .

No senators were more eager to get going than the four Democratic presidential candidates facing the prospect of being marooned in the Senate ahead of kickoff nominating votes in Iowa and New Hampshire.

“I’d rather be here,” said Vermont Sen. Bernie Sanders on New Hampshire Public Radio while campaigning Sunday in Concord.

During the trial, Sanders and other senators are required to sit for perhaps six grueling hours of proceedings daily — except Sundays, per Senate rules — in pursuit of the “impartial justice” they pledged to pursue. But there was scant evidence that anyone’s mind was really open about whether Trump earned vindication or ouster.

Mystery, however, abounded over the trial’s ground rules. Senate Majority Leader Mitch McConnell, R-Ky., shed no light on how the proceedings will follow — and differ from — the precedent of President Bill Clinton’s impeachment trial in 1999.

“The president deserves a fair trial. The American people deserve a fair trial. So let’s have that fair trial,” said Democratic Rep. Jason Crow of Colorado, one of the seven impeachment prosecutors.

But what’s fair is as vigorously disputed as the basic question of whether Trump’s pressure on Ukraine to help him politically merits a Senate conviction and removal from office. The stakes are enormous, with historic influence on the fate of Trump’s presidency, the 2020 presidential and congressional elections and the future of any presidential impeachments.

Whatever happens in the Senate, House Speaker Nancy Pelosi, D-Calif., has said, Trump will “be impeached forever.” Members of Trump’s team countered that if they win a vindication for Trump, it means “there will be an acquittal forever as well,” Trump attorney Robert Ray said Sunday. “That is the task ahead.”

For all of the suspense over the trial’s structure and nature, some clues on what’s to come sharpened on Sunday.

The president’s lawyers bore down on the suggestion that House impeachment is invalid unless the accused violated U.S. law. Dershowitz’s argument, backed up by Ray, refers to an 1868 speech by Benjamin Curtis, who after serving as a Supreme Court justice acted as the chief lawyer for Andrew Johnson at his Senate impeachment trial.

Johnson was ultimately acquitted by the Senate.

“The core of the impeachment parameters allege that crimes have been committed, treason, bribery, and things like that, in other words, other high crimes and misdemeanors,” Ray said Sunday.

Republicans have long signaled the strategy, which has, in turn, been disputed by other scholars.

“Rubbish,” said Frank Bowman, a University of Missouri law professor and author of his own book about the history of impeachment for the Trump era.

“It’s comically bad. Dershowitz either knows better or should,” said Bowman, who said he had been Dershowitz’s student as a law professor at Harvard.

Even as he made the case for Trump’s acquittal, Dershowitz on Sunday distanced himself from the rest of Trump’s defense team and said he would merely speak about the Constitution at the trial. He refused to endorse the strategy pursued by other members of that team or defend Trump’s conduct and said he didn’t sign onto the White House legal brief filed Saturday, which called impeachment a “brazen” attempt to overturn the 2016 election.

“I’m a liberal Democrat … I’m here as a constitutional lawyer,” Dershowitz said. “I’m here to lend my expertise on that issue and that issue alone.”

Democrats, meanwhile, are pushing for witnesses and documents that weren’t part of the House proceedings. A few Republicans said they want to know more before deciding. It’s relevant because new information from Lev Parnas, an indicted associate of Trump lawyer Rudy Giuliani, is being incorporated in the House case. At the same time, Senate Democrats want to call John Bolton, the former national security adviser, among other potential eyewitnesses, after the White House blocked officials from appearing in the House.

With Republicans controlling the Senate 53-47, they can set the trial rules — or any four Republicans could join with Democrats to change course.

Crow spoke on CNN’s “State of the Union” and Dershowitz was on CNN and ABC’s “This Week.” Ray was on Fox News Channel’s “Sunday Morning Futures.” Schiff appeared on ABC and Nadler on CBS’s “Face the Nation.”