For the most part, Donald Trump’s obstruction of Congress has been going as he expected: A committee subpoenas a witness or requests documents and he claims executive privilege or — as he began doing just last week — claims that anyone who worked for the administration has “executive immunity,” meaning they don’t have to show up to testify.

Executive immunity, it should be noted, is total bullshit, as Daily Kos noted just last week when the issue came up:

“‘It’s important to distinguish between executive immunity and executive privilege,’ former U.S. Attorney Barbara McQuade explained on an episode of the podcast Talking Feds. McQuade recalled that George W. Bush’s White House tried to claim executive immunity to block his former White House Counsel, Harriet Miers, from having to testify about a scandal involving the mass firing of U.S. Attorneys. As McQuade noted, that argument tanked in court, with a federal judge ruling that top aides to Bush weren’t immune from congressional subpoenas.”

And now we have Annie Donaldson, the former chief of staff for Don McGahn, who was Trump’s White House counsel until October of last year, seeing through the administration’s lies and agreeing to cooperate with the House Judiciary Committee. Committee chairman Rep. Jerry Nadler (D-NY) announced Monday that Donaldson will indeed agree to testify:

“Ms. Donaldson had a front row seat to many of the instances outlined in the Mueller Report dealing with President Trump’s alleged obstruction of justice and other abuses of power, which is why she is a key witness for the committee in our ongoing work to hold the president, his associates, and members of his administration accountable.”

Donaldson, who is pregnant and currently living in Alabama, will initially submit written responses to questions from the judiciary committee, and then personally appear in November, after her child is born.

Make no mistake, Donaldson could indeed be a key witness for congressional investigators, as she has first-hand knowledge of whether or not the president committed obstruction of justice and other crimes, all of which could well rise to the level of high crimes and misdemeanors.

Just Security recently called Donaldson a “prized witness” for Congress, adding:

“Donaldson knows as much about Trump’s campaign against the Special Counsel as anyone, and in some ways, she is more poised than either Mueller or McGahn to shed new light on the President’s misconduct. The Office of the Special Counsel cited her notes and testimony nearly 70 times in its report, despite her removed role in the key events the Special Counsel examined. Donaldson’s appearance in the report shows how critical her testimony may be to a determination of whether the President abused his powers.”

Remember the name Annie Donaldson. When the history books are written, she — much like John Dean in the Nixon administration — may well be the one person who winds up bringing a premature end to a corrupt and criminal president’s time in office.