If you’re a U.S. citizen: CBP cannot deny you entry to the United States merely because you refuse to unlock the phone. If you’re a non-citizen seeking admission: refusal is much riskier.
The important wrinkle is that CBP’s published policy expressly guarantees that a person being admitted as a U.S. citizen won’t be denied entry solely because CBP couldn’t inspect the device. It doesn’t give lawful permanent resident (green card holders) that same explicit statement. Instead, it says refusal by a “foreign national” can be considered in an admissibility determination.
Isn't the guarantee for citizens a bit stronger than CBP's policy? I don't think they can lawfully deny entry of a citizen, period.
They cannot (lawfully) deny entry. But they can admit you and then immediately detain and/or arrest you.
Sure, if they have a warrant or probable cause, just like any other law enforcement officer.
In theory, yes, but in practice they can do whatever they want, and suing them after the fact is going to be expensive, and have a high probability of not working out for you.
When interacting with border officials (or any LEOs, for that matter), be polite, don't get hostile or aggressive, but also be firm and don't volunteer any information that you're not required to give.
this only applies if they don't refuse to acknowledge your papers as valid and/or they haven't previously put you on some hidden list of people of interest, in which case the instance where you get to prove you're who you say you are will be mediated, like the rest of the (as per the current system) nonpeople, by as many layers of humilliation and risk to your life and health as they can place.
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