Let's be honest. They'll detain anyone who looks like they can't prove citizenship on the spot in the vicinity. Absolutely despicable. What can we do to stop or at least impede this?
ICE operates under rules that say they're not supposed to detain people at church. So encourage people to spend raid day at church.
Don't help out. Give the absolute minimum, don't provide information, and refuse to give access on the basis of an administrative warrant (one not signed by a judge)
At a bare minimum, if you get questioned about a neighbor or coworker, "I don't know" and "I can't recall" are your go-to's, no matter how benign the question may seem.