President Donald Trump's penchant for ditching his loyalists when it's politically expedient may soon net House Democrats a star witness for impeachment. After previously refusing to cooperate with the probe, Ukrainian-American businessman and Rudy Giuliani crony Lev Parnas has signaled that he's now willing to work with impeachment investigators, including responding to requests for records and testimony. “We will honor and not avoid the committee’s requests to the extent they are legally proper, while scrupulously protecting Mr. Parnas’ privileges including that of the Fifth Amendment,” Parnas's lawyer Joseph Bondy told Reuters, who first reported the news Monday.

Parnas, who was recently indicted with associate Igor Fruman for alleged campaign finance violations, had previously refused to comply with the impeachment inquiry after being subpoenaed by the House. Former attorney John Dowd said in a letter to lawmakers that their request was “overly broad and unduly burdensome,” and claimed that “the Democratic Committee members’ intent is to harass, intimidate and embarrass my clients.” But while Fruman reportedly continues to stonewall the investigation, Parnas apparently had a change of heart after being spurned by Trump, who claimed not to know Parnas and Fruman in the wake of their arrest. “I don’t know them. I don’t know about them. I don’t know what they do,” Trump told reporters.

This response was clearly unacceptable to Parnas, a failed businessman turned GOP sycophant who has gone all in on Trump since he first announced his candidacy in 2015. Along with Fruman, Parnas has donated hundreds of thousands of dollars to Trump and other Republicans; used his ties to Trump and Giuliani to advance his business interests; and become a fixture at Trump rallies and the president's Washington D.C. hotel, where he and Fruman spent $13,000 within one five-week span in September and October 2018 alone. Through his devotion to the president, Parnas claims to have built a relationship with the man himself, who he's been photographed alongside or shown at events with multiple times. (When asked about being photographed with Parnas and Fruman, Trump told reporters, “I have a picture with everybody.”) “I’m a businessman who obviously is close to [Giuliani], is close to the President,” Parnas told the New Yorker in October. “I love the President. I love the Administration. I fully support him and honestly think he is going to go down as probably one of the greatest, if not the greatest, Presidents ever.” To hear his beloved president pretend not to know him, then, was apparently too much for Parnas to bear, spurring his decision to cooperate with an inquiry that Trump has decried as a “witch hunt” and a “hoax.” “Mr. Parnas was very upset by President Trump’s plainly false statement that he did not know him,” Bondy told the New York Times about the reasoning behind Parnas's about-face.

Parnas's decision to comply with the impeachment inquiry comes as many of the president's White House confidants and high-profile allies continue to resist the probe, including Giuliani. But even with so many others resisting, Parnas's likely participation in the investigation is sure to be a big boon for Democrats, given the outsized role that he and Fruman reportedly played in the Trump administration's dealings with Ukraine. The two men worked with Giuliani in his quest to persuade Ukrainian officials to investigate Joe Biden and son Hunter Biden, including introducing Giuliani to and arranging talks with former Ukrainian prosecutors Yuriy Lutsenko and Viktor Shokin. (Shokin's 2016 firing after investigating Burisma, the Ukrainian gas company employing Hunter Biden, is at the heart of the—baseless—Ukraine conspiracy theory, while Lutsenko was once Giuliani's main ally in his attempts to persuade Ukraine to do Trump's bidding.)