WASHINGTON — President Trump’s White House declared war on the Democrats’ impeachment inquiry Tuesday evening, vowing a “full halt” to any cooperation going forward.

But the letter Trump sent Congress to justify his stance hardly has the trappings of a serious legal memo: It reads more like a Trumpian rant that’s been translated into fancy lawyer speak by the White House counsel’s office, said legal experts who reviewed the document.

“It’s a political argument dressed up in legalese,” said William Howell, an expert on the presidency and separation of powers at the University of Chicago.

That's going to present a problem for Trump when his stonewalling hits the courts.

“Invalid”

Trump’s White House blasted the inquiry as “invalid” for a litany of reasons, including several that don’t stand up well to close legal analysis.

“Given that your inquiry lacks any legitimate constitutional foundation, any pretense of fairness, or even the most elementary due process protections, the Executive Branch cannot be expected to participate in it,” reads the letter signed by White House Counsel Pat Cipollone and sent to House Speaker Nancy Pelosi and other Democratic leaders on Tuesday night.

The White House lawyer argues the current impeachment inquiry isn’t legit because it wasn’t approved by a vote from the full House, and dismisses Pelosi’s announcement kick-starting the process in late September as “nothing more than a press conference.”

But there’s no requirement for any such vote in the Constitution, which gives the House leadership wide latitude for how to run impeachment proceedings.

“In the past, there’s been a resolution that said, ‘go forth and investigate,’ but frankly, that’s just a formality,” said Frank Bowman, author of “High Crimes and Misdemeanors; A History of Impeachment for the Age Of Trump.”

“Due Process”

Trump’s White House lawyer accused the House of trampling over “fundamental fairness and constitutionally mandated due process” in the impeachment inquiry.

“For example, you have denied the president the right to cross-examine witnesses, to call witnesses, to receive transcripts of testimony, to have access to evidence, to have counsel present and many other basic rights guaranteed to all Americans,” Cippolone wrote.

But again Trump’s team seems a bit confused. For starters, those points are generally rights afforded to a suspect in a criminal trial — not to the president during an impeachment proceeding in the House of Representatives.

Impeachment by the House more closely resembles the process of being indicted by a grand jury, where witnesses testify in secret so they can speak freely while prosecutors decide whether to bring criminal charges.

If the House votes to impeach, Trump will then face trial in the Senate before he’s either cleared or kicked out of office.

“There are no due process rights stipulated in impeachment hearings — they just don’t exist,” said Howell. “This is about removing an individual from office, and it’s not about putting somebody in jail. The consequences, and the standards, are very different.”

Ultimately, Trump's unhinged letter may end up doing him more harm than good. Democrats have already signaled that they plan on citing Trump's blanket defiance as yet another reason to evict him from the presidency.

Democrats are weighing whether to impeach Trump over his efforts to pressure Ukraine to launch an investigation of his 2020 Democratic rival Joe Biden, including on a phone call with Ukraine’s president on July 25.

“If they are stonewalled now, they’ll take it as further evidence of obstruction,” Richard Arenberg, a former Hill staffer for Democrats, told VICE News. “And they can drop all that evidence into a second article of impeachment.”

Pelosi appeared to receive Trump’s letter as precisely that kind of material.

“This letter is manifestly wrong,” Pelosi said in a statement. “The White House should be warned that continued efforts to hide the truth of the President’s abuse of power from the American people will be regarded as further evidence of obstruction.”