1975 United States v. Brignoni-Ponce-"likelihood that any given person of Mexican ancestry is an alien is high enough to make Mexican appearance a relevant factor."
1982 AZ state court- State v. Graciano that "enforcement of immigration laws often involves a relevant consideration of ethnic factors."
Think about it for a second. How often do INS agents go to places where people are EXPECTED to be illegal and check ID? How about ALL THE TIME.
This isnt about whether it is legal or constitutional. This is a political and ideological battle right now. The left position is that there should be NO ENFORCEMENT of illegal immigration. California, AZ, Now Colorado...its all the same.