A friend of my mother is a Polish immigrant to the US who is now a citizen. “Greta” is flying back to Poland to visit her ailing mother, but she’s terrified that Customs will find a reason not to let her back in. I say that as long as she has a valid US passport, she could have Covid virions yeeting out of her eyeballs and the worst that could happen is that she’s put into quarantine at a hotel in [arrival city] until further notice.
Could a US citizen be denied entry into the US for any reason?
The ACLU says US citizens have a right to enter the US. Customs, etc. can make it a hassle, or potentially arrest you if they think you have committed a crime, but they can’t legally make you leave.
No. Basically, a US citizen, which I presume she is, can not be denied entry for any reason. She could be arrested or detained for something, or in your example, she could be quarantined (in the US), but she couldn’t be denied entry.
Really, just have her Google this as there are tons of citations for this, including the ACLU link iamthewalrus_3 gave above. Or have her simply go back and look over the material she studied when she immigrated from Poland initially.
Other folks have (correctly) noted that if present yourself to US Customs and you’re a US citizen, you might be arrested or quarantined, but you won’t be turned away.
However, this presumes that the airline will let you board the plane in the first place. In particular, airlines are responsible for verifying that you have a negative COVID-19 test before boarding the plane (or documentation that you’ve recovered from COVID-19 within the last 90 days). They also have to verify that you have the appropriate passport/visa you need to enter the USA. The government can impose fines on an airline for every passenger who is turned away from US Customs for whatever reason.
So if a US citizen contracts COVID-19 in a foreign country, they would be “stuck” in that country, because no airline would let them board a flight home. This would be a temporary situation, of course — they would eventually be able to return once they had recovered — but it wouldn’t be a fun experience.
Immigration (not Customs) won’t turn away a valid US citizen at the boarders. As others have said, letting you in the country doesn’t not equal letting you go free, but it doesn’t sound like there would be any reason for Immigration to have a problem with your mother’s friend.
It is possible for a naturalized US citizen to have their US citizenship revoked. But the process would involve court hearings, not something that would occur while she’s out of the country.
The material people study when immigrating has very little to do with their rights as citizens. Naturalization is handled by USCIS, which is part of the DHS. Border entry for citizens is handled by the State Department, as it issues passports.
The last thing they tell you before you take the Oath of Allegiance (during a naturalization ceremony) is that you shouldn’t plan any overseas travel for at least 90 days because you’ll need to obtain your U.S. passport.
The citizenship test includes some very broad information on the rights of U.S. nationals, but nothing about border crossings. Just stuff like “what is one right protected by the First Amendment?”