There was a “scientific consensus,” they told us.

According to the media and assorted experts, there couldn’t be any questioning of the idea that the coronavirus emerged naturally, and anyone who suspecting it might have come from a Chinese lab was an ignoramus. These enforcers believed in the power of the words “scientific” and “consensus,” when conjoined and used as a weapon, to shun dissenters and stifle debate.

During much of the pandemic, they were proven right. But the rigid conventional wisdom around the question of the origins of the virus has broken up, and evidence pointing to a lab leak is finally getting serious consideration.

A Wall Street Journal report underlined the foolishness of the old conformity. The report noted that according to U.S. intelligence, three researchers from the Wuhan Institute of Virology fell ill and went to the hospital in November 2019, right around the time the virus is believed to have begun spreading in the city.

And no less an authority than Dr. Anthony Fauci has now reversed himself and no longer rules out the lab theory.

The science writer Nicholas Wade wrote a long article that was a breakthrough in the debate. He noted that a letter in The Lancet in February 2020 and another letter in Nature Medicine a month later had huge roles in ruling the lab theory out-of-bounds, even though the missives were flawed.

The media nonetheless referred constantly to the letters to insist that the scientists had spoken. In much of the press, the Wuhan lab theory was taken about as seriously as the Chinese claim that the virus might have escaped from a lab at a military base in Maryland.

The orthodoxy, though, hasn’t been able to withstand the weight of counterevidence.

If the coronavirus jumped naturally from bats to another animal to humans, there should be some indication of that. But, as Wade points out, no one has found the original bat population or an intermediate species.

Likewise, the caves where the bats are thought to have been infected with the virus are about 1,000 miles from Wuhan, while the lab in the city was conducting dangerous coronavirus research.

It’s not as though a lab leak is a scenario out of science fiction. Wade notes it is dismayingly common: “The smallpox virus escaped three times from labs in England in the 1960s and 1970s, causing 80 cases and three deaths. Dangerous viruses have leaked out of labs almost every year since.”

The Chinese could help the cause of determining the origins of a virus that has created so much suffering and dislocation by not acting as if they had something to hide. Instead, they have been about as forthcoming about the Wuhan lab as they have about their activities in the Xinjiang region, site of the Uyghur genocide. The lab hasn’t shared its safety logs or other records, and no one should expect it to do so anytime soon. Both the natural and lab theories depend on guesswork. But one theory is now more plausible than the other, and it is the one that was scorned by people who sheathed their advocacy in science — and ignored everything to the contrary.