Gregory Greer was convicted at trial of possessing a firearm as a felon, and Michael Gary pleaded guilty to two similar offenses before the Supreme Court decided Rehaif v. United States. Neither proceeding required the government to prove that the defendant knew he was a felon when possessing the firearm. The Supreme Court held that the omission was plain error, but neither defendant showed a reasonable probability that the error affected the result. Both had multiple prior felony convictions, and neither represented that he would have offered evidence that he did not know his felony status. The Court rejected an automatic-reversal theory and held that Rehaif errors are ordinarily reviewed under the demanding plain-error framework when not preserved. It affirmed the Eleventh Circuit’s judgment for Greer and reversed the Fourth Circuit’s judgment for Gary. Justice Sotomayor concurred in part and dissented in part.