Frogprice, there's the rub.   You're stopped for a traffic infraction. What - other than skin color and/or accent - would give the officer "reasonable suspicion" that you're not a legal US resident?

And if anyone argues that since most illegals in AZ are Hispanics, that does not logically a basis for "reasonable suspicion."   The question is, "What proportion of those who "look" or sound "Hispanic" are illegal?"   If it could be shown that a high percentage of people with brown skin or a Spanish accent were undocumented immigrants, that might be cause for questioning most people like that, but I doubt that that is the case.