New Jersey has its own statutes, its own administrative agencies, and its own courts. So do the other states. States can use their law when something happens in or affects that state or the people involved in the state. When you are doing legal research about something that happened in New Jersey, you should probably start by finding New Jersey law. But if something happened in another state, you should start by finding that state’s law.
The U.S. Government has its own statutes, its own administrative agencies, and its own courts. This is called federal law. Sometimes you may need to find federal and not state law. The best way to figure this out is to check a secondary source by the topic of your question.
If you are looking at cases, read the case to see what question the court answered. Think about how similar your question is to the question the court answered. Think about how similar what happened to you is to what happened in the case. The more similar your question and facts are, the more helpful the case will probably be.