So, I am planning on getting my non-resident CCW from New Hampshire sometime this year. Not many states offer CCW to foreigners, but if you can get the NH one then you are good to go in many states.

My question is, if a non-US resident, say a tourist, intervenes in say a rape, attack, or mugging, and the criminal surrenders, would that foreigner/tourist be allowed to put that criminal under a citizens arrest? Because technically if I am not a US citizen, or a citizen of any US state, what authority do I have?

The criminal might be able to sue me for unlawful arrest/detention.

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