If you have committed a crime, you could end up in a state court in New Jersey or you could be tried at the federal level. It can help to understand the differences between state and federal crimes even if you are not facing a criminal charge because this is a confusing area that can be difficult to understand.
According to the Department of Justice, some crimes can be prosecuted at the state and federal levels because they are a violation of both state and federal laws. Some crimes are solely federal, such as mail fraud, tax crimes and crimes related to interstate commerce. If a crime falls within both state and federal jurisdiction, the U.S. Attorney General will work with prosecutors from the state to determine who will handle the case. It can be subjective.
If a case is handled by the U.S. Attorney General, then it is always tried in a federal court and under federal law. If a state prosecutor handles the case, then it is under the jurisdiction of the state and state laws. In addition, local prosecutors, such as those in your city, prosecute under the jurisdiction of state laws.
Due to the double jeopardy law, you cannot be tried in both federal and state court for the same crime. Only one court can take over prosecution of your case. Even if you are tried at the federal level and win your case, being found not guilty, the state cannot step in and try your case again. This information is for education and is not legal advice.