The most popular fact checks of 2021, so far

Technically not a fact check, this was one of the biggest hits in the 14-year history of The Fact Checker. Our timeline of key events, including important articles, helped readers understand why a theory once dismissed as nonsense — that the coronavirus that killed millions came from a lab in Wuhan, China — had gained new credence among scientists. Shortly after this column appeared, Biden ordered intelligence agencies to conduct a new review of the evidence. Without China’s full cooperation, however, the truth may never be known.