Arizona taking away constitutional rights?

[Danzig]

i thought the new law in az was to allow, or encourage, a policeman who suspects illegality, in this case immigration violations, to further investigate? seems like it would be just one more thing to check into-after all, no doubt your local sheriff is supposed to turn you in if the feds want you for other crimes, kidnapping for instance. why is it that local and regional police forces can handle a variety of crimes, but immigration violations are off limits? is this really that difficult a crime to investigate? what makes it so special? feds want you, they turn you over...u.s. marshals, same thing. state wants you, the locals hold you til the state comes and gets you....so what's the big deal about this?