So, I’m a lawyer, who deals with immigration though does not specialize in it. But here’s the thing(s):
1) Even someone who’s working could be here on a migrant (or other sort of) visa (hey, there are a few thousand per year, and *someone*’s got to get them, right?) or could be waiting for their case to resolve in immigration court, after having come to America to join a born or naturalized American family member.
2) Even people who are working improperly could have come into the country legally – and just overstayed their visa or be violating the conditions of their visa, and you have no idea what the niggly little regulations that govern that might be.
3) If a law enforcement officer asks you about a neighbor/friend/etc., take this moment to remind them that, unlike them, you cannot ask a random person off the street for their ID and be entitled to a response.
4) Even if someone has told you that they are undocumented, you still don’t know, do you? Humans lie all the time. How could you know for sure? You can’t, because they can’t prove that they have a lack of papers. Just because you haven’t seen papers doesn’t mean they don’t exist!
5) Don’t ever talk to cops in general. Why are you talking to a cop? Stop that, as soon as it is safe and feasible.
a very tired public defender