President Trump tried to fire special counsel Robert Mueller. That fact, reported Thursday night by the New York Times and confirmed by sources for the Washington Post and other papers, shreds the assurances from Republican lawmakers that Trump would never attempt such a thing. It also bolsters key elements of the case for impeachment. The aborted attempt to dismiss Mueller shows that Trump has sought to control the Russia investigation, that he has faked his reasons for disrupting it, and that he has ignored warnings that his behavior could be illegal.

The first thing that stands out is the flimsiness of Trump’s purported rationales for firing Mueller. According to the Times:

First, he claimed that a dispute years ago over fees at Trump National Golf Club in Sterling, Va., had prompted Mr. Mueller, the F.B.I. director at the time, to resign his membership. The president also said Mr. Mueller could not be impartial because he had most recently worked for the law firm that previously represented the president’s son-in-law, Jared Kushner. Finally, the president said, Mr. Mueller had been interviewed to return as the F.B.I. director the day before he was appointed special counsel in May.

What an odd list. The golf dispute, on its face, is trivial. There’s no record of Trump complaining about it in public, and, in fact, according to the Post, there’s no record of an exchange: “Mueller had sent a letter requesting a dues refund in accordance with normal club practice and never heard back.” So there’s no reason to think that Trump ever heard about it or that Mueller cared enough to follow up. The Kushner complaint is nonsensical. If anything, it implies that Mueller would be inclined to favor Trump. The same goes for the FBI job interview. When Mueller took the special counsel job, he was being wooed and flattered by Trump, not rejected.

If those rationales make no sense, where did they come from? Answer: Trump’s lawyers.

The Post and Times report that the weeks between Mueller’s appointment and Trump’s attempt to fire him, Trump’s lawyers were “compiling arguments about why Mueller could not be impartial” and “digging into potential conflict-of-interest issues.” That’s how they found the issue of the golf club refund.

So what was Trump’s real beef with Mueller? According to the Post, after Mueller’s appointment in May, Trump “spoke with a number of friends and advisers who convinced him that Mueller would dig through his private finances and look beyond questions of collusion with Russians. They warned that the probe could last years and would ruin his first term in office.”

That doesn’t prove Trump meant to obstruct justice. But it does show that when Trump tried to fire Mueller, the reasons he offered were fake ones concocted by his lawyers. And this echoes Trump’s behavior throughout the investigation. When Trump fired FBI Director James Comey, he initially claimed to base his decision on a memo from Deputy Attorney General Rod Rosenstein about the Hillary Clinton investigation. Then, in an NBC interview, Trump admitted that the Rosenstein story was an excuse. Trump said his real reason was that Comey was a “showboat” and was wrecking the FBI. Then we learned that a day after firing Comey, Trump had told the Russian foreign minister that Comey was a “nut job” and that Trump, by firing him, had relieved “pressure” on the U.S.-Russia relationship. Then it turned out that Trump, in his initial draft of the termination letter to Comey, had begun by calling the Russia investigation “fabricated and politically motivated.”

The second curious revelation in the Times story is that Trump didn’t just target Mueller directly. He also targeted Rosenstein. “Another option that Mr. Trump considered in discussions with his advisers was dismissing” Rosenstein, the paper reports, “and elevating the Justice Department’s No. 3 official, Rachel Brand, to oversee Mr. Mueller.”

This part of the story is significant because it shows that Trump’s concern was broader than any of the objections he raised against Mueller. Trump targeted Comey, Mueller, and Rosenstein. What did they have in common? It wasn’t golf fees or Kushner’s law firm. It was that they weren’t Trump’s men.

Look back over the Russia investigation, and you’ll see this pattern: Trump constantly sought control. In January 2017, he told Comey that he expected loyalty. A month later, Trump tried to stop Attorney General Jeff Sessions from recusing himself. Later, Trump fired Comey and rebuked Sessions for failing to protect Trump from the investigation. In July, Trump drew a red line around his personal finances and signaled to Mueller that he had better not cross that line. And in August, Trump called up members of Congress to derail legislation that would impede him from firing Mueller.

Third, the Times report shows that when Trump tried to fire Mueller, he did so despite warnings that this might be criminal. By May 22, it was widely reported that Mueller was obliged to investigate—and was, in fact, investigating—whether Trump had obstructed justice by firing Comey. When Trump moved in June to oust Mueller, he was essentially ignoring those reports.

Thursday night’s revelations indicate that Don McGahn, the White House counsel, may also have warned Trump directly that firing Mueller would be seen as obstruction. The Times says McGahn “refused” Trump’s instruction to fire Mueller, “saying he would quit instead.” Specifically, the Times says McGahn was “concerned that firing the special counsel would incite more questions about whether the White House was trying to obstruct the Russia investigation.” It’s hard to believe that McGahn didn’t convey to Trump this legal basis for refusing to comply. In addition, the Post reports that Steve Bannon and Reince Priebus, who served, respectively, as Trump’s chief strategist and chief of staff during these crucial weeks, “sought to enlist others to intervene with” Trump to stop him from firing Mueller. But Trump went ahead and “moved to remove” Mueller, the paper reports, “despite internal objections.” What exactly were those objections? How many people warned Trump that he might be breaking the law?

This, too, fits Trump’s known behavior. In May, when Trump drafted an initial termination letter to Comey, McGahn warned him not to send it. McGahn marked it up, removing problematic sections. In July, the spokesman for Trump’s legal team resigned, reportedly because he and other members of the legal team worried that Trump had obstructed justice by devising a false statement about the Trump Tower meeting with Russians. And last week, Axios reported that Comey’s successor, FBI Director Chris Wray, blocked Sessions’ attempt to make him fire FBI Deputy Director Andrew McCabe. Sessions reportedly pressured Wray on Trump’s behalf and dropped the attempt when Wray threatened to resign. Is it plausible that Trump wasn’t told, in any of these cases, that his own people saw his behavior as obstruction?

The latest reports also indicate that Trump’s aides knew his assault on Mueller was out of bounds. “The White House has denied nearly a dozen times since June that Mr. Trump was considering firing Mr. Mueller,” says the Times. In August, Trump’s White House counselor, Kellyanne Conway, insisted, “The president has not even discussed that.” Trump’s lawyer, John Dowd, said firing Mueller had “never been on the table, never.” This stonewall persisted despite repeated queries. Looking back, says Times reporter Maggie Haberman, “I’m a little surprised at how effective people in the White House were at lying to us about what was actually going on at the time.” But why the need to lie and lie, if the attempt to fire Mueller was nothing to be ashamed of?

To impeach and remove a president for obstructing justice, you need to show that his intent in targeting investigators was corrupt. The easy way is to find tapes in which he talks explicitly about orchestrating false testimony. The harder way is to show that he has repeatedly lied about his motives and has maneuvered to control the investigation, despite warnings to back off. Trump’s assault on Mueller, coupled with his previous assaults on Comey, Sessions, Rosenstein, and McCabe, solidifies that case. He obstructed justice.

Correction, Jan. 27, 2018: This article originally misstated that James Comey fired James Comey. Donald Trump fired Comey.