Can you rely on what White House officials say on behalf of the U.S. government to be true?

The answer, even by the account of President Trump himself, is no.

Of all the crises and controversies consuming this White House, perhaps none is more fundamental than the collapse of its credibility. And a close look at some of the administration’s policies, statements and controversies suggests chief responsibility of that collapse can be laid at the feet of the man who works in the Oval Office.

Take one of the latest dramas to play out in Washington, D.C.: whether Trump revealed highly classified secrets in a White House meeting with senior Russian diplomats, as alleged by The Washington Post on Monday.

Monday night, Trump dispatched National Security Adviser H.R. McMaster, who is held in high regard by leaders of both parties and by journalists, to knock down the story. McMaster called it false even as he confirmed much of the rough outline of the story.

And yet the questions intensified on Tuesday — not least because Trump himself tweeted that he had shared sensitive information with the Russians. Trump even noted that he is legally entitled to do so — which legal analysts largely say he is, because he is president.

So Trump directly undercut his own national security adviser’s statements on a controversy reaching a fever pitch in the nation’s Capital.

“The president has gladly used up [White House press secretary] Sean Spicer’s credibility,” says Nicole Wallace, the former communications director for President George W. Bush, a Republican. “He has trampled the credibility of [adviser] Kellyanne Conway. He has used up and sort of walked to the line of his vice president’s credibility. And now it is it is H.R. McMaster’s turn to expend his personal credibility in service of this president.”

Wallace’s assessment was echoed by a Democratic counterpart, Jennifer Palmieri, who was the communications director for President Obama and held a similar role for Hillary Clinton’s 2016 campaign. “It is incredibly damaging,” she tells NPR. “It’s not just about spokespeople — he’s hurting the credibility of the vice president and the national security adviser.”

Both former White House aides say that Trump began shredding his administration’s credibility from his first full day in office, when Wallace says Trump sent Spicer out to lie about the size of the crowds for his inauguration.

Spicer claimed the crowds for the ceremony broke all the records — a laughable assertion, driven by Trump himself, and easily disproved by pictures from the U.S. National Park Service.

“That would have been it for me,” Wallace says. “I would have said ‘Buh-bye. This isn’t going to work out’.”

“I like Sean Spicer,” says Wallace, now host of a new afternoon show on MSNBC called Deadline: White House. “I don’t believe anything he says from the podium. I just think he’s no longer a credible messenger.”

You know who else says you can’t believe what White House officials say?

The man whose Twitter handle is @realDonaldTrump, who tweeted last week: “As a very active President with lots of things happening, it is not possible for my surrogates to stand at podium with perfect accuracy!”

The kindest interpretation is that he’s saying everyone is human and therefore fallible. Assuredly, press aides of both parties have been sent out to spin mightily, putting the best light on uncomfortable moments.

This crisis of credibility falls in neither category. The Trump administration’s inability to convey information accurately or honestly exceeds anything seen in Washington in more than four decades.

Vice President Mike Pence twice has been shown to make false statements publicly on behalf of the president. On CBS’s Face the Nation in January, then vice president-elect Pence vouched for Trump’s first National Security Adviser, Michael Flynn, saying the aide had not spoken of sanctions with Russian officials on the day that the Obama administration put them in place: “I think to suggest that is to give credence to some of these bizarre rumors that have swirled around the candidacy.”

Acting Attorney General Sally Yates warned White House officials that wasn’t true — and that Flynn had been compromised by lying to Pence. But Trump kept him on for weeks. Flynn resigned in mid-February, conceding that he “inadvertently briefed the Vice President-elect and others with incomplete information regarding my phone calls with the Russian ambassador.” Trump tweeted that “the real story is leaks” — suggesting that he might not have required Flynn’s departure had the story of his contacts with the Russians not surfaced publicly.

Last week, Pence joined Spicer and Kellyanne Conway in asserting that Trump had fired FBI director James Comey because of a highly critical memo from deputy attorney general Rod Rosenstein.

“President Trump made the right decision at the right time to accept the recommendation of the deputy attorney general and the attorney general to ask for the termination of the director of the FBI,” Pence told reporters on Wednesday. (Rosenstein hadn’t in fact called for Comey’s dismissal, but his critique was profound.)

Pressed by a reporter, Pence also said Comey’s firing had nothing to do with the FBI investigation of the ties between Trump’s campaign and the Russian government — which includes Flynn and other Trump associates.

“That’s not what this is about,” Pence said.

Yet on the very next day, Trump contradicted just about everything that Pence had said, starting with the vice president’s claim of the central role the Rosenstein memo had played in deciding Comey’s professional fate.

“Regardless of the recommendation, I was going to fire Comey,” Trump said last Thursday in an interview with NBC’s Lester Holt.

Then Trump contradicted Pence by invoking the Russia investigation in explaining his decision-making process.

“When I decided to just do it, I said to myself — I said, ‘You know, this Russia thing with Trump and Russia is a made-up story’,” Trump told Holt. “It’s an excuse by the Democrats for having lost an election that they should’ve won.”

According to stories in The New York Times and elsewhere, Trump has blamed much of the current outrage seizing Washington on his press shop. Fox News’ Kimberly Guilfoyle, co-host of the prime-time show The Five, told the San Jose Mercury News that she has entered into talks with the White House about taking over Spicer’s job as press secretary.

Fox News later sent coordinated statements with Guilfoyle noting she was under long-term contract; she said her job was “tough to beat.” The network’s publicity office would not comment on whether Guilfoyle’s talks were dead, fictional or ongoing, which would mean she was auditioning for a job at the White House while being paid by a cable news channel. She appeared on Tuesday night’s episode of The Five, largely downplaying the administration’s troubles and questioning its critics.

“It’s just ridiculous to talk about a staff shakeup or changes in the communications team,” Palmieri says. “The stakes are too high. The pressure is too much. The scrutiny is too much. Eventually the truth is revealed, and the true core of your president comes to light.”

Palmieri spoke of addressing challenges such armed conflicts, natural disasters or epidemics.

“This is not just a game of who’s got the best message,” Palmieri says. “You’re speaking for the United States of America. It’s incredibly important — not just within our country but abroad — that we can rely on what is said by the White House press secretary, the vice president, and the national security adviser.”

Asked today whether he was concerned about the White House’s eroding credibility, Sean Spicer sidestepped, telling reporters no one would ever want that.

Credibility is of course an elusive and intangible quality, but it’s crucial for governing nonetheless.

Late Tuesday afternoon, The New York Times reported that Jim Comey had written a memo he shared with a small circle of colleagues saying that Trump had asked him to cut short the part of the Russia inquiry involving then national security adviser Mike Flynn. It has since been reported separately by myriad other news outlets, including NPR.

The Trump administration issued a statement saying that Comey’s account wasn’t true.

Yet during a credibility crisis, who will be willing to give this White House — or this president — the benefit of the doubt?

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