By David Leonhardt – The New York Times.

The ninth week of Donald Trump’s presidency began with the F.B.I. director calling him a liar.

The director, the very complicated James Comey, didn’t use the L-word in his congressional testimony Monday. Comey serves at the pleasure of the president, after all. But his meaning was clear as could be. Trump has repeatedly accused Barack Obama of wiretapping his phones, and Comey explained there is “no information that supports” the claim.

I’ve previously argued that not every untruth deserves to be branded with the L-word, because it implies intent and somebody can state an untruth without doing so knowingly. George W. Bush didn’t lie when he said Iraq had weapons of mass destruction, and Obama didn’t lie when he said people who liked their current health insurance could keep it. They made careless statements that proved false (and they deserved much of the criticism they got).

But the current president of the United States lies. He lies in ways that no American politician ever has before. He has lied about — among many other things — Obama’s birthplace, John F. Kennedy’s assassination, Sept. 11, the Iraq War, ISIS, NATO, military veterans, Mexican immigrants, Muslim immigrants, anti-Semitic attacks, the unemployment rate, the murder rate, the Electoral College, voter fraud and his groping of women.

He tells so many untruths that it’s time to leave behind the textual parsing over which are unwitting and which are deliberate — as well as the condescending notion that most of Trump’s supporters enjoy his lies.

Trump sets out to deceive people. As he has put it, “I play to people’s fantasies.”

Caveat emptor: When Donald Trump says something happened, it should not change anyone’s estimation of whether the event actually happened. Maybe it did, maybe it didn’t. His claim doesn’t change the odds.

Which brings us to Russia.

Russia’s interference in the 2016 presidential campaign was an attack on the United States. It’s the kind of national-security matter that a president and members of Congress swear to treat with utmost seriousness when they take the oath of office. Yet now it has become the subject of an escalating series of lies by the president and the people who work for him.

As Comey was acknowledging on Monday that the F.B.I. was investigating possible collusion between Russia and the Trump campaign, Trump was lying about it. From both his personal Twitter account and the White House account, he told untruths.

A few hours later, his press secretary, Sean Spicer, went before the cameras and lied about the closeness between Trump and various aides who have documented Russian ties. Do you remember Paul Manafort, the chairman of Trump’s campaign, who ran the crucial delegate-counting operation? Spicer said Manafort had a “very limited role” in said campaign.

The big question now is not what Trump and the White House are saying about the Russia story. They will evidently say anything. The questions are what really happened and who can uncover the truth.

The House of Representatives, unfortunately, will not be doing so. I was most saddened during Comey’s testimony not by the White House’s response, which I’ve come to expect, but by the Republican House members questioning him. They are members of a branch of government that the Constitution holds as equal to the presidency, but they acted like Trump staff members, decrying leaks about Russia’s attack rather than the attack itself. The Watergate equivalent is claiming that Deep Throat was worse than Haldeman, Ehrlichman and Nixon.

It fell to Adam Schiff, a Democratic representative from Southern California, to lay out the suspicious ties between Trump and Russia (while also hinting he couldn’t describe some classified details). Schiff did so in a calm, nine-minute monologue that’s worth watching. He walked through pro-Putin payments to Michael Flynn and through another Trump’s aide’s advance notice of John Podesta’s hacked email and through the mysterious struggle over the Republican Party platform on Ukraine.

“Is it possible that all of these events and reports are completely unrelated, and nothing more than an entirely unhappy coincidence? Yes, it is possible,” Schiff said. “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.”

Comey, as much as liberals may loathe him for his 2016 bungling, seems to be one of the few public officials with the ability and willingness to pursue the truth. I dearly hope that Republican members of the Senate are patriotic enough to do so as well.

Our president is a liar, and we need to find out how serious his latest lies are.