In 1993, Willie Tyler was charged by the state of Pennsylvania with murder and conspiracy to intimidate a witness. He was found not guilty of murder and guilty on the conspiracy charge. He served his sentence and was paroled. Shortly after he was released on parole, Tyler was charged in a four-count federal indictment that included the same charges for which he had been indicted in Pennsylvania. As relevant here, the federal district court denied Tyler’s motion to dismiss the indictment, rejecting Tyler’s argument that the federal government had violated his right under the Double Jeopardy Clause by seeking to try him for the same offense for which he had already been tried in state court. According to the district court, Tyler’s double jeopardy claim was foreclosed by Third Circuit and Supreme Court precedent, which permits a second prosecution for the same offense by a different “sovereign.” On appeal, the Third Circuit granted the government’s motion for summary affirmance. Tyler was convicted at trial, and asked the Supreme Court to reconsider its past decisions allowing successive prosecutions for the same offense by different sovereigns (i.e., the “dual-sovereignty doctrine”).

CAC, along with the Cato Institute, filed a friend-of-the-court brief in support of Tyler, urging the Court to grant review and hold that the dual-sovereignty exception to the Double Jeopardy Clause is inconsistent with the text, structure, and history of the Constitution. We argue that both the Double Jeopardy Clause and our federalist structure of government were adopted to protect individual liberty, and that the dual sovereignty exception to the Double Jeopardy Clause undermines this protection. As we explain, concerns about government overreach and harassment that the Double Jeopardy Clause was adopted to prevent are particularly important today, given the expansive scope of federal criminal law and the significant federal-state cooperation in criminal law enforcement.

Finally, our brief explains why changes in constitutional law that have occurred since the Court’s last review of the dual-sovereignty exception make review now particularly important. The dual-sovereignty exception was first adopted against the backdrop of a legal regime in which the Double Jeopardy Clause did not apply to the states. Whatever validity the doctrine may have had then, it has been completely undermined by subsequent decisions of the Supreme Court that recognize that the Fourteenth Amendment protects against state infringement of the personal rights guaranteed by the Bill of Rights, including the Double Jeopardy Clause.