At this point, it should come as no surprise that President Donald Trump has fired someone he’d spent the past few months praising. What should shock the conscience, and worry anyone concerned about the rule of law in America, is that Trump booted FBI Director James Comey for reasons relating to the octopus of an inquiry whose tentacles extend to the 2016 election, the administration’s Russia ties, Michael Flynn’s ethical shenanigans, and more. The time has now come for Congress to compel the appointment of a special counsel to investigate the Trump administration and its Russia ties, whether by holding up nominees, impounding the Trump administration’s budget, or some other combination of legislative pressure. And beyond the writ of that special counsel, Congress should begin its own broad bipartisan inquiry into the Trump administration’s war on justice. For politicians on the left and right, May 9, 2017, should be a day of reckoning. There are no shoes left to drop.

In the pantheon of political appointees who serve the president, the FBI director stands apart. All effectively serve as “at will” employees who may be fired for any reason, at any time. But due to the job’s 10-year tenure—one that’s deliberately designed to cross presidential terms—as well as the FBI’s sensitive role in society, we think of the bureau director as someone whose integrity is beyond reproach. The person ensconced in the position is supposed to be both supremely competent and completely apolitical, something of a cross between a federal judge and the chairman of the Joint Chiefs of Staff.

Of course, Comey was no mere FBI director. In 2016, he oversaw inquiries that affected both presidential candidates: one into Hillary Clinton for potential mishandling of classified information, the other into Trump’s campaign for potential collusion with Russian intelligence agencies. Comey revealed details about the former, much to Clinton’s detriment, and in apparent violation of Justice Department norms regarding the release of “derogatory information about the subject of a declined criminal investigation.” It remains unclear whether Comey’s disclosures affected the 2016 election outcome, though it would be surprising if it didn’t. Since the election, Comey did not step back and cede the spotlight. Rather, he brought attention to himself via his statements regarding 2016, his continuing pursuit of Russia-related national security investigations, and his dust-ups with the White House over Trump’s unsupported allegation that he was wiretapped during the 2016 campaign.

So, it’s a very big deal that Trump summarily fired Comey on Tuesday afternoon. In Washington, there are firings, and then there are firings. Although the Justice Department’s memorandum recommending Comey’s departure carries merit, the timing and tone of Trump’s own termination letter makes Trump’s intention clear: The president wanted this to be a public execution of the sort Voltaire described in Candide as something “to encourage the others.” Consider that Comey was dismissed by letter while he was speaking to FBI employees in Los Angeles. He learned of his own sacking by watching it on television—a fitting outcome given the president’s employment history.

The FBI director now joins acting Attorney General Sally Yates and former U.S. Attorney Preet Bharara as senior law enforcement officials who have been fired by Trump. While in office, Comey and Yates oversaw most of the tentacles of the investigative octopus looking into the Trump campaign, the Trump White House, and potential Russia ties. Bharara reportedly handled some parts of that octopus, too, and also would have exercised jurisdiction in the Southern District of New York over the Trump Organization. The seniority of these officials, and their potential investigatory relationship to Trump, suggests the most apt comparison here is to the “Saturday Night Massacre” initiated in 1973 by President Richard Nixon to try and block the Watergate investigation.

Why did Trump dump Comey now? All of the facts cited in the letters justifying Comey’s firing have been known for many weeks. The timing of his Tuesday termination suggests that Trump turned on him within the past few months, following the back-and-forth between Trump and Comey over whether the FBI (or some other agency) had wiretapped Trump during the 2016 campaign. Trump alleged as much in a tweet, but the entire intelligence community and Justice Department refused to back up the president. Comey went further, asking the Justice Department and the White House to publicly withdraw Trump’s statement, ostensibly to buttress the apolitical credentials of the FBI as it continued to pursue its Russia-related inquiries. For Trump, it seems, the matter continued to burn.

The legal cover for Comey’s firing came via a memo written by Rod Rosenstein. The deputy attorney general, who was confirmed on April 25, came to the Department of Justice with a sterling bipartisan reputation from decades in public service and a promise to the Senate Judiciary Committee to impartially oversee pending inquiries into Trump and Russia following Attorney General Jeff Sessions’ recusal from these matters. Two weeks later, Rosenstein recommended Comey’s termination. It’s unlikely that any president, of any party, could have ignored the language and recommendations of Rosenstein’s letter, though it remains unclear at this stage whether the deputy attorney general weighed Comey’s merits with anything resembling real independence. Either way, the language in the Rosenstein memo was sober—far more sober than Trump’s own pointed letter, one that at once chided Comey for an erosion of “public trust and confidence” in the FBI while highlighting the director’s supposed assurance “on three separate occasions, that I am not under investigation.” This was a letter guaranteed to shock the system, and to make every federal official at every level think twice about crossing the president.

Trump’s treatment of Comey may ultimately backfire. Even if Trump had legitimate reason to fire Comey—and he arguably did—his targeting of the one person in government capable of bringing down his presidency is suspicious on its face. Trump’s timing and tenor will lead anyone who’s paying any attention to suspect this was about more than the director’s corrected testimony regarding Clinton emails.

James Comey had the institutional position, investigative resources, and personal power to stand up to Trump and thoroughly investigate him and his associates. Now, Comey is gone, and no amount of hand-wringing can unfire a presidential appointee. If Congress cares about the rule of law, it must act quickly and decisively. It also must ensure the next FBI director is even more competent and ethical than the one who just got axed, because trying times lie ahead.