Question

Criminal trials for charges of murder and other serious crimes would be conducted in the state court system unless the charges involved multiple states, non-citizen immigrants, or a foreign ambassador state court system unless the investigation of the case involved the highest executive agencies in the state federal court system unless the investigation of the case required a majority of state resources federal court system unless the charges were limited to actions that violated state laws

Answer 1

The first answer is correct.
Serious crimes are conducted in the state court system unless the charges involve multiple states, non-citizen immigrants, or a foreign ambassador.

Answer 2

I believe the answer is: state court system unless the charges involved multiple states, non-citizen immigrants, or a foreign ambassador

Multiple state criminal actions usually thrown to the federal court system, violation by Non-citizens immigrants is usually punished directly by deportation, and foreign ambassadors cannot be prosecuted in any way since the law in foreign country is not applicable to them.