Like it or not the Supreme Court ruled LONG AGO that the constitution applies to everyone, citizen, non-citizen, etc. There are a few exceptions to that such as the right to vote.
So only Mexicans are illegal? What about all the Russian illegals I deal with on a daily basis? They don't matter?
How do you know if someone is illegal by looking at them? Are you saying that anyone that looks Hispanic should be stopped and checked for papers? I am somewhat brown (browner in the summer!
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) if I am stopped and accused of being illegal I have no way to prove otherwise. I don't carry papers with me because I don't have any to carry. I have a License, but again, that does not list citizenship on it. So can I be held for a few days while they do a full background check on me? I was born in this country, as were my parents and grandparents.
Stopping to search someone for their citizenship status is a violation of the 4th Amendment unless that person is stopped with probable cause (traffic stop, etc) Probable cause is not the person is brown and looks like they are Hispanic.