This article has been updated.

On Monday afternoon, Attorney General William P. Barr instructed security forces standing between the White House and a large group of vocal, peaceful protesters to begin moving the demonstrators away from the area. There was an urgency to it; President Trump was going to be speaking a few minutes and planned to visit a church located in the middle of the protest area. Within minutes, law enforcement officials including members of the Interior Department’s Park Police began forcibly pushing protesters away, using riot shields, mounted officers, batons, explosive devices and tear gas. A bit later, Trump emerged from the White House, posed for a few victorious photos with a Bible borrowed from his daughter and then went back to the White House.

There are two ways in which the Trump administration objected to this presentation of what happened. The first was to argue that somehow Barr’s instructions were unrelated to Trump’s walk, an argument which even Barr didn’t directly reject when asked Thursday. (He claimed that there was an existing plan to extend the secure area around the White House but didn’t deny that the immediate need for doing so was Trump’s visit to the church.) The other, and more vocal objection centered on a very specific detail: reports of the use of “tear gas.”

Reporters and protesters on the scene were very clear that some sort of irritant had been deployed. Eyes stung, people were coughing. The pool report from the day, the update from the White House press corps journalist tracking the president that day, noted that she and others were affected by the need to cough as they joined Trump on his trip to the church. Video from the effort to move the protesters shows clouds of smoke swirling around those in the vicinity. A reporter from WUSA found a canister on the ground with markings indicating that it had been used to deploy tear gas.

Park Police, though, claimed that no tear gas had been used.

“USPP officers and other assisting law enforcement partners did not use tear gas or OC Skat Shells to close the area at Lafayette Park,” a statement released Tuesday read. Instead, officers “employed the use of smoke canisters and pepper balls.”

With that, Trump and his defenders were off to the races. A movement largely predicated on skepticism about the claims made by federal law enforcement insisted that reporters who were present were somehow wrong about what had happened and used the conflict between what the reporters experienced and what the Park Police said as evidence that the media was lying — and, by extension, biased against the president.

Again, it was an odd thing to focus on, given the scale of the events Monday and what they suggested about the willingness of the White House and its security to use force to disrupt a legal protest. But it was something to focus on, at least, so they did.

“It’s said that a lie can get halfway around the world before the truth can get its pants on. This tear gas lie is proof of that,” a statement from Tim Murtaugh, the communications director for Trump’s reelection, read. “For nearly an entire day, the whole of the press corps frantically reported the ‘news’ of a tear gas attack on ‘peaceful’ protestors in Lafayette Park, with no evidence to support such claims.”

Murtaugh and the campaign immediately began peppering media outlets with insistent demands for corrections to their reports about the use of tear gas. The campaign’s aggressive social media presence used a statement from White House press secretary Kayleigh McEnany to disparage reporters as “fake news” for asking about tear gas.

“No one was tear-gassed. Let me make that clear,” McEnany said in a news briefing on Tuesday, just over a month after she pledged never to lie to reporters. She went on to insist that the area was cleared only because protesters had turned violent — coincidentally after Trump had already decided on visiting the church.

The Federalist, a sharply conservative outlet which has become a prominent voice in the pro-Trump media universe, wrote a lengthy article attacking the media for “falsely” claiming that tear gas had been used.

“Prior to getting the actual facts, nearly every major media outlet falsely reported that canisters of tear gas, not smoke canisters, were used against peaceful protesters,” the site's Mollie Hemingway wrote. “The false story spread internationally despite its lack of evidence.” Dozens of examples of the media referring to the use of tear gas were listed.

The conclusion? “The entire narrative the media glommed onto in lockstep was that Trump was a monster who tear-gassed peaceful protesters to do something meaningless,” Hemingway wrote.

Trump, of course, loved these defenses. He amplified Murtaugh's statement and shared Hemingway's article multiple times. He even praised her in an interview with Fox News host Brian Kilmeade, calling Hemingway “a real reporter, a great journalist.” That was in contrast to the media who reported on the use of tear gas, who are “corrupt and they're fake."

Fox News, somewhat surprisingly, didn’t bring up the controversy very much. That may be in part because the network also didn’t cover the clearing of the protesters very much. On Fox Business, though, perennial Trump fan Lou Dobbs bashed the media for accusing the government of deploying tear gas.

After reading the Park Police statement, Dobbs summarized the situation earlier this week.

“There was never any tear gas,” he said, before offering another bit of good news for the president: “On Wall Street, stocks today rallied and rallied big time."

This idea that there was no tear gas depended entirely on the statement from the Park Police and on the vagueness of the term “tear gas.” As The Washington Post reported Wednesday, though, even the Centers for Disease Control and Prevention identifies the sort of devices that the Park Police admitted using as a form of tear gas. It was a specific, organic iteration of irritant, but it was a qualifying irritant nonetheless.

On Friday, the Park Police themselves clarified. Yes, they’d used a form of tear gas.

“I think the term ‘tear gas’ doesn’t even matter anymore,” Park Police spokesman Sgt. Eduardo Delgado told Vox. “It was a mistake on our part for using ‘tear gas’ because we just assumed people would think CS or CN” — shorthands for types of tear gas which use chemical compounds. The Park Police’s use of pepper balls was classified as OC: that organic version which results in a similar reaction.

“I’m not saying it’s not a tear gas, but I’m just saying we use a pepper ball that shoots a powder,” Delgado said.

Again, this was obvious based on the reporting at the time. Experienced journalists encountered the irritants being used to clear the area and understood that it was tear gas. They reported as such. The Trump campaign and the president’s defenders seized upon the semantic distinction being drawn by the Park Police as an effort to distract, however much they could, from the events of Monday afternoon, challenging the media’s accuracy by highlighting a flawed assertion.

This shift from Monday to Friday does highlight one way in which the media is disadvantaged in a struggle to share accurate information. When the Park Police insisted that no tear gas had been used, media outlets were forced to seek out more evidence of what had been deployed. (WUSA later reported, for example, that it found CS canisters on-scene as well — further undermining the Park Police assertions.) The Trump campaign is under no ethical obligation to evaluate its comments or to offer any sort of correction to its audience for being wrong in the way members of the media would have been.

Regardless, the new comments from the Park Police essentially brings the debate to a close. Meaning that analysis of what happened Monday can focus on the deployment of security forces using weapons and irritants to clear a peaceful protest so that the president could have a photo op, instead of the particulars of which irritants were used.

Update: On Friday afternoon, the National Park Service released a statement on behalf of the acting chief of the Park Police addressing Delgado’s interview. It simply reiterated the original statement.

“United States Park Police officers and other assisting law enforcement partners did not use tear gas or OC Skat Shells to close the area at Lafayette Park in response to violent protestors.”

In short order, deputy press secretary Judd Deere shared the statement on Twitter.

It’s worth noting not only that this conflicts with Delgado’s statement and that it continues to rely on a more-limited definition of what constitutes “tear gas,” but that one of the canisters found by the WUSA reporter Monday was specifically a “Skat Shell,” as shown below.

Later on Friday, Barr told the Associated Press that the Park Police was already in the process of clearing the square when he arrived. That contradicts the original Park Police statement in which it was claimed that the prompt for clearing the square was violent acts by protesters well after Barr arrived.

In other words, the administration contradicts the Park Police statement even as that statement constitutes the entire body of evidence that no tear gas was used.