In the case of Fong Foo et al. v. United States, 1961, the Supreme Court ruled in favor of the petitioners who were previously convicted for conspiracy to defraud and other related offenses against the U.S government. The District Judge had directed acquittals on all counts due to lack of evidence during their trial but a federal appellate court reversed this decision stating that it was an error by the judge as there was enough evidence for conviction. However, when brought before the Supreme Court, they held that once a judgment of acquittal has been made - even if based on an egregious legal error - it constitutes a final verdict and cannot be appealed or reviewed without putting defendants at risk for double jeopardy which is prohibited under Fifth Amendment rights. Therefore, despite any errors made by lower courts in directing an acquittal prematurely or erroneously, such decisions are conclusive and immune from judicial review.

In the dissenting opinion for Fong Foo et al. v. United States, Justice Harlan argued that the majority's decision to uphold a directed verdict of acquittal as final and unreviewable was incorrect. He contended that this ruling could potentially allow trial judges to abuse their power by arbitrarily directing acquittals in favor of defendants, thereby undermining the role of juries in criminal trials. Furthermore, he believed that such a precedent would prevent appellate courts from correcting these potential abuses of judicial discretion because they would be unable to review or reverse directed verdicts of acquittal under any circumstances. In his view, this interpretation contradicted both common law principles and constitutional guarantees for fair trials.