Doesn't prosecuting someone in federal court for an offense they were acquitted of in state court violate double jeopardy?
Under a doctrine known as the separate sovereigns doctrine or the dual sovereignty doctrine, two separate government entities successively prosecuting someone for the same offense is said not to violate the prohibition on double jeopardy. While this doctrine has stood for quite some time, it is still an area of ongoing dispute and litigation.
The foundations separate sovereigns doctrine in American jurisprudence trace back more than 150 years. The United States Supreme Court laid the groundwork for upholding the separate sovereigns doctrine in the case of Fox v. Ohio (1847). It ruled in this case that both the federal government and state governments had jurisdiction "over offences against the current coin of the United States" and both could punish violators.
Soon thereafter, it reaffirmed this general concept of dual sovereignty in United States v. Marigold (1850) and Moore v. People (1852).
Later in the Prohibition-era case of United States v. Lanza (1922), the Court explicitly ruled that, "When the same act is an offense against both state and federal governments, its prosecution and punishment by the latter, after prosecution and punishment by the former, is not double jeopardy within the Fifth Amendment." It upheld this precedent in the subsequent case of Hebert v. Louisiana (1926).
In Abbate v. United States (1959), and Bartkus v. Illinois (1959), the Court upheld the doctrine both when the defendant was convicted in the court of one of the sovereigns and re-prosecuted by the other, and when the defendant was acquitted in the court of one of the sovereigns and re-prosecuted by the other.
At this point, the doctrine was well established when the two sovereigns in question were the federal government and a state government. In the case of Wheeler v. United States (1978), the Court refused to limit dual sovereignty to successive state and federal prosecutions only. Instead, it held that the Double Jeopardy Clause does not bar prosecution of a Native American tribe member in a federal district court after having been convicted in a tribal court of a lesser included offense arising out of the same incident.
The Supreme Court in Heath v. Alabama (1985) once again upheld the dual sovereignty doctrine, explicitly rejecting the "suggestion that the dual sovereignty doctrine be overruled and replaced with a balancing of interests approach". It further applied the dual sovereignty doctrine to "successive prosecutions by two States for the same conduct".
Despite all of these Supreme Court rulings, legal challenges to the separate sovereigns doctrine continue at the highest level of the American legal system. In December 2018, the United States Supreme Court heard oral arguments in the case of Gamble v. United States (2018) challenging the separate sovereigns justification for putting someone in double jeopardy by prosecuting them for the same offense in courts under two different jurisdictions. A decision in this case is expected in 2019.