While the Chinese government denies the possibility of a lab leak, its actions tell a different story. The Chinese military posted its top epidemiologist to the Institute of Virology in January. In February Chairman Xi Jinping urged swift implementation of new biosafety rules to govern pathogens in laboratory settings. Academic papers about the virus’s origins are now subject to prior restraint by the government.

In early January, enforcers threatened doctors who warned their colleagues about the virus. Among them was Li Wenliang, who died of Covid-19 in February. Laboratories working to sequence the virus’s genetic code were ordered to destroy their samples. The laboratory that first published the virus’s genome was shut down, Hong Kong’s South China Morning Post reported in February.

This evidence is circumstantial, to be sure, but it all points toward the Wuhan labs. Thanks to the Chinese coverup, we may never have direct, conclusive evidence—intelligence rarely works that way—but Americans justifiably can use common sense to follow the inherent logic of events to their likely conclusion.