Thanks for the post, but the statutes you listed relate to law enforcement and INS dealings with already-arrested individuals, which is not the topic of the poll.
I agree with your examplesin 29 unless the area would be within a city limit. Probably not apply to a national park. I do know that if a federal crime is committed at the airport in LA the police department can make an arrest because it is within the city of LA. The penal code also authorizes the cops to arrest on public offenses within the city limits.
The LAPD has a policy not to act on the citizenship status of those they detain or arrest. They hold them the precinct cells until they release or transfer to county jail. They are being challenged on this POLICY. The decision to release or transfer is based upon the possible crime irrespective of the crime of how they entered the country. The jails are under the jurisdiction of the county.
Your comments about the chief is your usual............