The feds are yet again trying to have their cake and eat it too, this time regarding constitutional criminal procedure. The Double Jeopardy Clause prevents the government from using its immense resources to prosecute criminal defendants twice for the same crime. Still, if a defendant’s first trial results in a hung jury, or the conviction is reversed on appeal, the trial is a legal “non-event” and the government can seek a new trial. If the defendant is acquitted, however, then no new trial is possible; the acquittal precludes a second try because that would be “double jeopardy.” In a new case out of Puerto Rico, the government is trying to claim that acquittals can also be “non-events” that allow retrial. Juan Bravo-Fernandez and Hector Martinez-Maldonado received a mixed verdict at trial: they were acquitted on two the charges—conspiring and travelling to bribe a member of the Puerto Rican Senate—but convicted of the actual bribery. But the two acquittals necessarily depended on a finding that neither defendant violated the bribery statute. Indeed, the U.S. Court of Appeals for the First Circuit vacated the bribery conviction because the jury’s verdict was improperly based on invalid instructions from the trial judge. That left one vacated conviction and two acquittals that logically required a finding of “not guilty” on the bribery charge. At that point, double jeopardy should have kicked in; the acquittals precluded a retrial regarding the underlying bribery. As the Supreme Court said in Yeager v. United States (2009), any “apparent inconsistency between a jury’s verdict of acquittal on some counts and its failure to return a verdict on other counts” does not “affect the preclusive force of the acquittals under the Double Jeopardy Clause.” But the trial and appeals courts found that this precedent did not prevent retrial here. The Supreme Court has now taken up the case and Cato has filed an amicus brief supporting the defendants. We argue that the government’s position is contrary to the common law of double jeopardy and misunderstands the effect of a court’s having vacated a conviction that cannot stand given other acquittals. When a court vacates a ruling in the double-jeopardy context, the effect is to wipe it out as if it never existed. Going back to Sir William Blackstone and English common law, if a “judgment, pronounced upon conviction, [wa]s falsified or reversed, all former proceedings [we]re absolutely set aside, and the party st[ood] as if he had never been at all accused,” for better and for worse: He was “restored in his credit, his capacity, his blood, and his estates,” but he was also “liable to another prosecution for the same offense.” Yet here the government seeks the have the vacated conviction stop the preclusive effect of acquittal. The government cannot benefit from the vacating “non-event” that enables a retrial while at the same time arguing that it is also an “event” such that the acquittals don’t count in the double-jeopardy calculus. Moreover, allowing the First Circuit’s decision to stand would give prosecutors more incentive to overcharge the same underlying conduct with multiple counts, forgive them for pursuing dubious theories of criminality, and permit them to use trials as dress rehearsals for future successive prosecutions—as well as impugning the inviolate nature of jury acquittals. These concerns strike at the heart of the Double Jeopardy Clause. That’s why we urge the Supreme Court to prevent the government’s attempt to overreach its prosecutorial authority by eviscerating a well-established, logical set of legal doctrines.