As I understand it, local police have jurisdiction over murders in their State. If the crimes cross State lines, the FBI may get involved (or if the victim is a federal employee, etc).
What would happen if several murders are discovered in one State, all believed to have been committed by the same person, yet the victims are from different States? Would the FBI assume jurisdiction? Or would it still depend on the LA police requesting their help?
For example, let’s say five bodies are found in LA, and the victims are discovered to be residents of other States? Let’s assume they were killed in LA (otherwise I assume that if they were killed/abducted elsewhere and then dumped in LA the crimes would cross federal lines and thus be open for FBI involvement).
In the above scenario, could the local police work alone? I realize they may actually need the extra manpower of the FBI.
Hope this is clear. Any help would be appreciated.