Originally Posted by
84fiero
I would hope that the government doesn't just take someone's uncorroborated word for it (maybe unless they have a number of friends, family, etc. saying "yep I used to blaze it with that guy every day"). But what are the situations where the government goes to the effort of interviewing family, friends, co-workers, etc. of a foreign citizen in, or arriving to, the US? Does it occur for green card applicants or those going down the citizenship path? It seems like whatever those circumstances are would be about the only common situations where it's even theoretically a concern that someone would "rat you out" or that a private communication would surface, aside from some other Federal dealings that aren't common for most non-citizens.
Otherwise if, as noted before, there is no public record of it, there's just no realistic way the government will ever find out. They don't send out investigative field teams for every tourist or short-term business visitor or similar, who comes to the US.
Two relatives of mine were sponsored by my family to come to the US. When they arrived at MSP for their first trip to the US, we got called by CBP’s predecessor at the airport and were asked to confirm some information, none of which involved drug use; and there was some back and forth. Later, when the same relatives were changing their immigration status for the third+ time, there was another effort made to confirm some of the same sort of information asked by CBP’s predecessor and/or State. While it is very far from common, it’s possible and does still happen.
That said, it’s been very uncommon for LPR status and — even way more extremely rare — naturalization status to be undone due to discovery of material misrepresentations made earlier during an application seeking travel and/or entry/admission and/or change of immigration/citizenship status. But it can happen, and it may just require some in the relevant positions of authority to want to make it an issue and it could become an issue even as it may not have been a priority or even considered relevant for many years or decades before.