This, the act or acts violate multiple laws of two sovereigns.
A knocks B over the head with a 2x4 in Ohio. Throws him in a trunk and drives to Indiana. And then murders B and dismembers the body and buries it
Ohio can prosecute for assault and battery, plus kidnapping.
The United States can prosecute for kidnapping and murder resulting from that kidnapping.
Indiana can prosecute for murder and abuse of a corpse.
Ohio can prosecute for assault and battery, plus kidnapping.
The United States can prosecute for kidnapping and murder resulting from that kidnapping.
Indiana can prosecute for murder and abuse of a corpse.
See my previous comment from Post #16. There is no damn good reason for the U.S. to prosecute anyone in this case. The kidnapping took place in Ohio. The murder took place in Indiana. Prosecuting those two crimes should be sufficient to render justice in this case.
Aside from the constitutional issues, you run into a practical problem in having multiple prosecutions for the same alleged crime. In the example you cited, there is a distinct possibility that someone is prosecuted in Federal court in a kidnapping-murder case where the defendant has been acquitted of kidnapping in Ohio and acquitted of murder in Indiana. That itself is bad enough, but this chain of events also introduces the possibility that the Feds will prosecute a kidnap-murder case where another culprit who has no connection to the Federal defendant is later convicted of the crime in Ohio and/or Indiana.
This is the kind of crap that leads to a total loss of respect for the law.
Yup, there are all kinds of scenarios where both the state and the feds have separate causes of action.
The United States is made up of 50 sovereign states. A conviction in one state for a specific act or crime should act as a bar to all other states and the federal government. And a conviction in federal court would be a a conviction by all states.