Has anyone ever heard whether or not it is a violation of the 4th Amendment to approach a few hispanic individuals waiting for a bus patiently and demand papers? Isn't this a violation of the constitution?

It is quite normal for BP to do that especially on states where there are BP station.In California,Arizona, new Mexico, Texas that always happen and it is understandable since there are some who really have no papers and one cannot claim violation of his/her rights' violated since s/he is not a US citizen or resident.

I've done a lot of research on this issue -- it is not as clear cut as it sounds and the law is very complicated and fact-specific. If anyone is particularly interested, post and we can chat.