At the event in Tulsa, Oklahoma, where thousands of seats remained empty despite expectations of overcrowding, Trump called coronavirus testing "a double-edged sword" and claimed that he had told advisers to "slow the testing down, please."
"When you do testing to that extent, you're going to find more people, you're going to find more cases, so I said to my people, 'Slow the testing down, please,'" Trump said, joking that so many tests are being conducted "that people don't even know what's going on."
"We got another one over here," he said, pointing into the crowd. "The young man is 10 years old. He's got the sniffles. He'll recover in about 15 minutes. That's a case!"
Trump's remark, which echoed previous erroneous claims he has made about testing, came under fire soon after. A senior White House official told NBC News that Trump "was clearly speaking in jest to call out the media's absurd coverage" of the pandemic.
Speaking on CNN's "State of the Union," top White House trade adviser Peter Navarro said Trump's comment "was tongue-in-cheek."
"Come on now. Come on now. That was tongue-in-cheek. Please," Navarro said. "I know it was tongue-in-cheek. That's news for you, tongue-in-cheek."
Navarro later called the comment "a light moment" for Trump "in a rally."
On CBS' "Face the Nation," acting Homeland Security Secretary Chad Wolf said the comment was the result of "frustration" over the media's focus on "an increasing case count."
"And we know that that's going to occur when you test individuals more and more and more," Wolf said.
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However, many areas with higher case counts are also seeing increased hospitalizations and spiking positive test rates, figures health experts use to measure the severity of an outbreak.
Former Vice President Joe Biden, the presumptive Democratic presidential nominee, and his campaign were quick to push back.
"More than three months ago, Donald Trump claimed that 'anybody that wants a test can get a test.' This was a lie — one that cost thousands of lives," deputy campaign manager Kate Bedingfield said in a statement. "Tonight in Tulsa, the President explained why America lagged so many other nations in testing: because he 'said to my people slow the testing down please.'"
Biden tweeted: "Speed up the testing."
Speaking with "Fox News Sunday," Biden campaign senior adviser Symone Sanders said Trump's "debacle of a rally last night will long be remembered."
Sanders pointed to the campaign's requirement that attendees sign waivers absolving the campaign of liability should they get sick with COVID-19 at the rally.
"But I think the most damning thing from that rally last night was, in fact, the president's admission that he said to his people to slow down the testing," she said. "This is an appalling attempt to lessen the numbers only to make him look good. So I think that's what will be remembered long after this debacle of a rally — the admission of the president that he slowed testing for his political benefit and not for the American people."
Trump is "not concerned with public health," Sanders said. "He's concerned with his ability to hold a rally."
In a statement Sunday, House Speaker Nancy Pelosi, D-Calif., said Trump's "efforts to slow down desperately needed testing to hide the true extent of the virus mean more Americans will lose their lives."
Atlanta Mayor Keisha Lance Bottoms, a Democrat, said on "State of the Union" that the rally was an "embarrassment" and that "this is no time to joke."
"Even if it were a joke, which it was not, it was an inappropriate joke," she said. "Do you think the people, the 120,000 families out there who are missing their loved ones, thought it was funny?"
After Trump and his campaign hyped up the potential for a massive crowd, his campaign was left to explain why a crowd that was supposed to have been so large that it required an overflow stage outside BOK Center instead failed to fill much of the venue.
While BOK Center holds more than 19,000 people, the Tulsa fire marshal told NBC News that only 6,200 supporters occupied the general admission sections.
Multiple people close to the White House said Trump was "furious" at the "underwhelming" crowd.
"The fact is that a week's worth of the fake news media warning people away from the rally because of COVID and protesters, coupled with recent images of American cities on fire, had a real impact on people bringing their families and children to the rally," campaign manager Brad Parscale said. He also pushed back on reporting that TikTok users and K-pop fans signed up en masse as a joke, artificially inflating registration numbers.
"Every rally is general admission — entry is on a first-come, first-served basis, and prior registration is not required," he said. He didn't address the large numbers of empty seats.
Parscale had excitedly promoted that 1 million people had RSVP'd, setting high expectations for the crowd. Tulsa officials said last week that they were prepared for about 100,000 people. At the White House last week, Trump himself promised a sellout, saying, "We've never had an empty seat, and we certainly won't in Oklahoma."
Trump was originally scheduled to speak to overflow crowds outside the arena, but his campaign told NBC News moments before the rally began that the president wouldn't make that appearance. Very few supporters had gathered in the area ahead of the rally.
On "Fox News Sunday," Trump campaign senior adviser Mercedes Schlapp also claimed that Trump supporters were scared off by protesters.
"I'm telling you, there were people and families that ... couldn't bring their children because of concerns with the protesters," Schlapp said.
Host Chris Wallace responded: "We're showing pictures here, and it shows big, empty areas. Frankly, it makes you guys look silly when you deny the reality of what happened.”
Schlapp said that "we're not denying the reality" of the crowd size but that she would "love to see a Joe Biden rally."
On the other hand, a senior Trump adviser told NBC News: "This was a bad night for our effort."
"Hardly a deal-breaker, lots of time to go, many miles ahead," the adviser said. "But everything was awful tonight: crowd size, lack of focus in the speech, way too many riff stories."
The potential for the rally to be a COVID-19 "superspreader" event drew a lot of attention in the lead-up. Just before the rally, six Trump campaign members and Secret Service agents in Oklahoma tested positive for COVID-19. They were immediately quarantined and didn't attend. Just last week, Tulsa County experienced a 100 percent spike in coronavirus cases.
Speaking on "Fox News Sunday," Dr. Tom Inglesby, director of the Center for Health Security at the Johns Hopkins Bloomberg School of Public Health, said "the rally was concerning in terms of public health risk."
Even though the upper deck was mostly empty, supporters were tightly packed into some spaces in the lower bowl. And, as Inglesby said, the riskiest gathering is one that is large and indoors, where people can't socially distance and where people travel to and from out of town.
"And this rally met all of those criteria," he said. "And what I saw was that people were sitting quite close to each other — didn't see very many people wearing masks."