In most shooting cases regardless of the situation, as long as a firearm was discharged and someone was killed/injured, most jurisdictions will either take the shooter(s) into custody or at minimum will question them as part of the "investigation". I tell my students that if they are EVER involved in a shooting, that they seek the advice of a competent attorney. Don't answer ANY questions directly related to the case until they have an attorney present, AND have been cheked out by medical professionals. (Stuff like "Why did you shoot?", "Did you feel like you were in danger?", etc.) I advise them to cooperate with law enforcement, but don't admit anything and don't say anything that could remotely be used against them in the future.
gf