At 6:35 A.M. on Monday, a few hours before the House Intelligence Committee convened its first public hearing on Russian involvement in the U.S. election, President Donald J. Trump asserted once more that the issue was nothing more than an elaborate political distraction. “This story is FAKE NEWS and everyone knows it!” he tweeted, adding, a short time later, “The Democrats made up and pushed the Russian story as an excuse for running a terrible campaign. Big advantage in Electoral College & lost!” He went on, “The real story that Congress, the FBI and all others should be looking into is the leaking of Classified information. Must find leaker now!”

Less than forty minutes into the hearing, James Comey, the director of the F.B.I., provided the latest official confirmation that the “Russian story” is not “FAKE NEWS.” It is, rather, the most serious legal scandal to confront a sitting President in nearly two decades. In an extraordinary public statement, Comey disclosed not only that the bureau is investigating Russian meddling in the campaign but that it is also looking at what relationship the Trump campaign might have had to that meddling. “The F.B.I., as part of our counterintelligence mission, is investigating the Russian government’s efforts to interfere in the 2016 Presidential election,” Comey said. “And that includes investigating the nature of any links between individuals associated with the Trump campaign and the Russian government, and whether there was any coördination between the campaign and Russia’s efforts.” Comey, who had previously avoided confirming the existence of the investigation, acknowledged that it had become a matter of public interest to do so.

Things did not end there. A few minutes later, answering questions from the committee, Comey calmly delivered yet more damaging news for the White House. Asked if he could confirm Trump’s tweets on March 4th that Barack Obama took steps to “tapp my phones” during the election, Comey said, “I have no information that supports those tweets.” Sean Spicer, the White House press secretary, has tried to source his boss’s fiction to a Fox News pundit’s remark that Obama relied on British intelligence agencies to conduct the surveillance. Fox itself has renounced that claim, and British intelligence officials have called the assertion “nonsense” and “utterly ridiculous.” On Monday, Mike Rogers, the head of the National Security Agency, who testified alongside Comey, was asked whether he agrees with the British view, and his answer was “Yes, sir.” (Asked on Monday afternoon whether Trump will apologize for his remark, Sean Spicer said no.)

Last year, Comey was lambasted by Democrats for releasing information during the campaign about his agency’s investigation of Hillary Clinton’s private e-mail server—for him, Monday’s hearing solved some problems while probably creating new ones. It demonstrated his independence and credibility at a moment when many wondered if he would be free to operate under the pressures imposed by Trump. But, because he also disclosed that the investigation of the Trump campaign began in July, Democrats will now want to know more about why he decided to inform voters about developments in the Clinton probe while keeping the Trump matter a secret.

For the White House, which in recent weeks has urged intelligence and law-enforcement officials to parrot its skepticism about the “Russian story,” Comey’s public acknowledgement of the probe makes it all but impossible to meddle again without risking serious political and legal consequences. The sharp rebuke from the director of the F.B.I. also presents Trump with a new kind of predicament. In nearly fifty years as a businessman, Trump operated largely outside the levers of ordinary accountability: he had a large inheritance to fall back on, the Trump Organization had no board of directors, and he employed a small staff. If one of his businesses went pear-shaped, the consequences were relatively private and recoverable; the tabloids lampooned him, but the public stakes were low. There was, often, another bank to turn to, another building to buy. An F.B.I. investigation is different. This investigation may last months or years, it cannot be escaped via distraction, and any effort to interfere or slow-walk or obstruct it will only invite more problems.

The last major legal scandal to face a sitting President began in 1995, when President Bill Clinton had an affair with an intern. Nearly three years later, on December 19, 1998, Clinton was impeached by the House of Representatives, on grounds of perjury to a grand jury and obstruction of justice. He was, of course, not driven from office, but the cloud of scandal made everything about running the country more difficult. Trump, too, now confronts the prospect of a Presidency shaped not only by the events to come but by past events that he cannot change.

Monday’s hearing also made clear where Democrats on the Intelligence Committee intend to focus, to the degree that they, as members of the minority party, will be able to shape the probe. Adam Schiff, the ranking Democrat, offered a time line of known contacts between Trump associates and Russian representatives, and of efforts by the Trump campaign to signal its support for Russian foreign-policy objectives. He mentioned the softening of language concerning Ukraine in the G.O.P. platform; the failure by the Attorney General, Jeff Sessions, to tell the Senate about his meetings with the Russian Ambassador; and the former Trump adviser Michael Flynn’s efforts to cover up his conversation with the same Russian Ambassador. Schiff also said that he was seeking to verify some of the claims found in a dossier of raw intelligence produced by a former MI6 agent named Christopher Steele, who had been hired by Trump’s political opponents prior to the election. “Is it a coincidence that the Russian gas company Rosneft sold a nineteen-per-cent share after former British intelligence officer Steele was told by Russian sources that Carter Page was offered fees on a deal of just that size?” Schiff asked at one point.

Some of the claims in the dossier may prove difficult to confirm—and, if refuted, they could embolden critics of the investigation to portray it as overly political—but Schiff seemed determined to use his time to persuade members of the public that they must consider the possibility of an underlying conspiracy at work. “Is it possible that all of these events and reports are completely unrelated, and nothing more than an entirely unhappy coincidence?” he asked. “Yes, it is possible. But it is also possible, maybe more than possible, that they are not coincidental, not disconnected, and not unrelated, and that the Russians used the same techniques to corrupt U.S. persons that they have employed in Europe and elsewhere. We simply don’t know, not yet, and we owe it to the country to find out.”

The Republican chairman of the Intelligence Committee, Devin Nunes (left), questioned James Comey about the F.B.I. investigation into Russian interference in the 2016 election. PHOTOGRAPH BY MARK PETERSON / REDUX FOR THE NEW YORKER PHOTOGRAPH BY MARK PETERSON / REDUX FOR THE NEW YORKER

Republicans on the committee, meanwhile, took a different approach. Devin Nunes, the Republican chairman, focussed not on the campaign or Russia but on leaks to the media. Tom Rooney, of Florida, pressed Mike Rogers on how many people had access to transcripts of Flynn’s phone calls with Ambassador Sergey Kislyak. Trey Gowdy, of South Carolina, led Comey down the road of whether reporters could be prosecuted for publishing classified information. This partisan tug-of-war—over witnesses, subpoenas, and investigative resources—will likely be a drama that continues in the months ahead.