On Monday evening, National Security Adviser H.R. McMaster stood in front of the White House and tried to discredit a Washington Post story. The story said that President Trump, in a meeting on Wednesday with Russian Foreign Minister Sergey Lavrov and Russian Ambassador to the U.S. Sergey Kislyak, had “revealed highly classified information” that “jeopardized a critical source of intelligence on the Islamic State.”

McMaster read carefully from a written statement. “The story that came out tonight, as reported, is false,” he said. He went on to describe what had been said in the meeting, and he asserted that other people who had been there, including Secretary of State Rex Tillerson, would back up his account. These witnesses, McMaster argued, were more credible than the unnamed “current and former U.S. officials” cited by the Post. “Their on-the-record accounts should outweigh those of anonymous sources,” McMaster said.

It’s reasonable to question the reliability of anonymous sources. Putting your name on what you tell the press is one way to help readers assess your credibility. When you refuse to be named, you shield yourself from direct accountability. If you tell one story anonymously, and a named source tells a different story, thereby putting his skin in the game, that person seems more credible.

But that isn’t what happened here. The dispute over the White House meeting isn’t just between anonymous sources and named public officials. It’s between specific claims and evasive nondenials. The Post’s sources have made factual allegations that can be checked. The administration hasn’t.

In the search for truth, falsifiable claims are a gesture of good faith. They stake the source’s credibility with the Post, and the Post’s credibility with its readers, on something that can be investigated. But McMaster and other Trump defenders don’t engage such claims. Instead, they issue “on-the-record” statements couched in cagey language that can’t be checked. These statements are worse than anonymous. They are vacuous.

The Post’s sources make numerous empirical claims. As reported by the paper, these include:

Trump “revealed the city in the Islamic State’s territory where [a] U.S. intelligence partner detected [a] threat.” (This revelation “jeopardized a critical source of intelligence on the Islamic State.”) What Trump revealed is “code-word information,” a top-level category of intelligence. The information “had been provided by a U.S. partner through an intelligence-sharing arrangement.” This partner “had not given the United States permission to share the material with Russia.” In the meeting, Trump boasted, “I get great intel. I have people brief me on great intel every day.” After the meeting, in an attempt at damage control, Trump’s assistant for homeland security and counterterrorism, Thomas Bossert, “placed calls to the directors of the CIA and the NSA.” “One of Bossert’s subordinates also called for the problematic portion of Trump’s discussion to be stricken from internal memos and for the full transcript to be limited to a small circle of recipients.”

Several of these claims have been repeated by officials who spoke anonymously to the New York Times, Wall Street Journal, BuzzFeed, and CNN, among others. It’s not clear whether the officials who talked to these outlets are the same ones who talked to the Post, but it’s likely that they overlap, since they assert inside knowledge of a sensitive meeting. So it’s fair to argue that the follow-up reports aren’t corroboration. But what’s striking is the absence of falsification or even dispute. None of the claims made by the Post’s sources have been rebutted.

Contrast this record with the administration’s response. The White House has released three statements. McMaster says the Post story, “as reported, is false,” but he doesn’t debunk any specific claim in the story. He says “it didn’t happen,” but he doesn’t say what “it” is. The empirical claims he makes—for example, that “at no time were intelligence sources or methods discussed”—are compatible with the Post report, which alleges not that sources and methods were explicitly discussed, but that they were inadvertently exposed by Trump’s disclosures.

The other two statements released by the White House are equally hollow. Dina Powell, the White House deputy national security adviser, says: “This story is false. The president only discussed the common threats that both countries faced.” Again, the factual claim fits the Post story, and the denial is too vague to check. A third statement, issued by Tillerson, doesn’t even say the Post story is false. It just says the people in the meeting “did not discuss sources, methods or military operations.”

To be fair, that last claim by Tillerson is falsifiable. Indeed, it seems false. According to McMaster, Trump “did not disclose any military operations that were not already publicly known.” It’s hard to imagine why McMaster would add the caveat about “not already publicly known” unless Trump had, contra Tillerson, discussed military operations.

On Tuesday morning, Trump himself weighed in. “As President I wanted to share with Russia (at an openly scheduled W.H. meeting) which I have the absolute right to do, facts pertaining to terrorism and airline flight safety,” he tweeted. Trump’s tweets, like his subordinates’ statements, didn’t challenge the Post’s reporting.

A few hours later, at a White House briefing, reporters asked McMaster what elements of the Post story were false. He ducked the question, instead disputing what he called the story’s “premise”: that what Trump had said in the meeting was “inappropriate.” He was then asked about four claims in the story: that Trump had shared classified information, that he had revealed the city where the crucial intelligence was obtained, that the information he shared came from a U.S. intelligence partner, and that Bossert had subsequently contacted the CIA and NSA. McMaster disputed none of these allegations.

These “on-the-record accounts” from Trump, McMaster, Tillerson, and Powell don’t outweigh the anonymous accounts of officials who spoke to the Post, the Times, the Journal, BuzzFeed, and CNN. That’s because Trump, McMaster, Tillerson, and Powell have carefully avoided saying anything that contradicts the Post story in a way that can be checked. Putting the names of public officials on such slippery nondenials doesn’t make them more credible than the Post’s reporting. It’s just another way of avoiding accountability.

Update, May 16, 2017, at 12:38 p.m.: This article has been updated with information from McMaster’s White House briefing, which took place after the piece was initially published.