Something unusual happened early last week, one of those things that only in retrospect stands out as noteworthy.

At a Sept. 28 White House event centered on expanding rapid testing to schools and other facilities, President Trump made some remarks from a lectern in the center of the White House Rose Garden. He wasn’t the only speaker: Several others, including the official in charge of the federal coronavirus testing program, also offered comments. But they spoke from a different lectern, one that was about 10 feet away.

This is not how it normally works at the Trump White House. The two-lectern setup is safer from a social distancing standpoint, but such things haven’t traditionally been at the forefront of concern at events Trump has attended. Two days before, speaking from the same spot, the president shared the lectern with his Supreme Court pick, Amy Coney Barrett, a more typical approach for him. But at that Monday event, a different approach.

Maybe this was a function of the subject. It’s not ideal to talk about a deadly viral pandemic while ignoring a central recommendation aimed at limiting the virus’s spread. That hasn’t stopped the White House in the past, of course — leading to another theory.

Did Trump already know that he might have contracted the virus?

The public didn’t learn of Trump’s diagnosis until he tweeted about his and the first lady’s positive tests early Friday morning. In retrospect, we could have inferred it a few hours earlier, when Trump called into Sean Hannity’s Fox News show and repeatedly mentioned pending test results for himself and Melania Trump.

“I just went out with a test. I’ll see what — because we spend a lot of time,” he said, referring to the amount of time he spent with his adviser Hope Hicks, who had tested positive earlier in the day. “And the first lady just went out with a test also. So whether we quarantine, or whether we have it, I don’t know."

Two more times, he said something similar: He and the first lady were awaiting results, and we’d just have to see what happens.

This has been the benchmark the administration has used for Trump’s infection. He apparently felt a bit under the weather Wednesday, but it wasn’t until that test late Thursday that his infection was confirmed. Trump traveled to Bedminster, N.J., earlier in the day Thursday, one of a number of events last week where other people might have risked infection from the president. Can we safely assume that Trump’s infection hadn’t been confirmed before that trip? Or the fundraiser in Minnesota on Wednesday? Or at Tuesday’s presidential debate? Or at that Rose Garden event Monday, the one with the separated lecterns?

In July, White House press secretary Kayleigh McEnany called Trump “the most tested man in America.” The president was “tested more than anyone, multiple times a day,” she said, though she later walked that back. So it seems as though it would be pretty easy to simply share that Trump last tested negative on, say, Wednesday, helping establish a baseline for his illness and aiding the effort to trace any contacts he made while infected.

But the White House has repeatedly declined to say when Trump last tested negative.

On Saturday, his personal physician, Sean Conley, was asked that question.

“I’m not going to get into all the testing going back, but he and all the staff or team routinely are tested,” Conley replied.

On Sunday, McEnany said something similar when speaking briefly with the press.

“I’m not going to give you a detailed readout with timestamps every time the president’s tested,” she said. “He’s tested regularly, and the first positive test he received was after his return from Bedminster.”

She wasn’t wearing a mask during that interaction. On Monday, she revealed that she, too, was positive for the virus.

That same day, Conley again refused to share information about Trump’s test history.

“I don’t want to go backward,” he said. Later, he claimed that Trump’s right to medical privacy precluded his sharing the information.

In fact, there have been very few times that Trump or the White House has acknowledged that he’s taken a test — only about a half-dozen in total.

Trump’s first known test was in mid-March, after he hosted President Jair Bolsonaro of Brazil at Mar-a-Lago shortly before an aide to Bolsonaro tested positive. On March 16, Trump revealed that he had tested negative.

It’s worth noting that, a week earlier, he rejected the idea that he needed to get a test.

“I spoke to the White House doctor — terrific guy, talented guy — he said he sees no reason to do it,” Trump said then, referring to Conley. “There’s no symptoms, no anything.”

In early April, Conley released a memo documenting another test, again negative.

By early May, Trump was touting having been tested “a number of times.” On May 18, he said he was being tested “every couple of days.” Three days after that, he offered his most infamous summary of his test results, saying that he’d recently “tested positively toward negative, right? So, no, I tested perfectly this morning, meaning — meaning I tested negative.”

That was it, save one interaction in early July. South Dakota Gov. Kristi L. Noem (R) had been in contact with someone who’d tested positive for the virus and then flew on Air Force One with Trump. McEnany was asked why Noem was allowed to do so and if Trump had tested negative since the flight.

“Yes, the president is tested constantly,” McEnany replied, “has tested negative, and those around him are tested as well.”

In the moment, that reads as vagueness, perhaps unfairly. It was two weeks later that McEnany touted Trump as the “most tested man in America” — an effort to rebut questions about why he refused to wear a mask when in public.

That the White House can’t or won’t reveal when Trump’s last negative test was conducted suggests one of three possibilities.

The first is that there’s concern about revealing the president’s personal information, which seems a bit like closing the barn doors after the horse is already at the glue factory.

The second is that Trump actually wasn’t tested as regularly as the White House has implied, reinforcing speculation that the safety net in place to prevent an outbreak was porous — speculation bolstered by the recent spate of confirmed cases in the executive mansion.

The third is that Trump was known to be positive earlier in the week but went ahead with planned events anyway.

Both of those latter possibilities introduce problematic political concerns, not to mention moral ones. Did the president knowingly put people at risk despite a positive test? Or did he put them at risk by accident, because he wasn’t being tested as often as was claimed?

Hence the question about those lecterns. Did Trump already know something then that the rest of us — including the Democratic presidential nominee and attendees at several fundraisers — wouldn’t learn until Friday? And, if not, why won’t the White House simply answer the question?