Feds sue Arizona over state immigration enforcement law

The Obama administration has sued the state of Arizona over the state's new law regarding questioning suspects in lawful contact with police (e.g. Terry stop) about possible illegal immigration. As is usual with culture wars issues, emotion trumps reason and facts, and there is lots of heat being generated--but little light. The law is, at least in part, an emotional reaction to frustration caused the inability or unwillingness of the feds to control illegal immigration. Laws based on emotional reactions are often, but not always, unwise. The way I, and others interpret the law, is that there must already be a lawful reason for the officer- citizen contact before the inquiry about citizenship is made. The inquiry about citizenship can then only be made on reasonable suspicion. The way I read existing 4th Amendment and Equal Protection law, ethnicity alone can never justify police intervention. The law does not authorize anything that some state officers in AZ and elsewhere have been doing lawfully for years. The Fourth Amendment and Equal Protection clause and numerous anti-discrimination and anti-profiling laws are available, at least on paper, to prevent abuses. Is it a good policy? Will there be widespread abuse? Who knows! Given that the law has yet to be enforced and that this is an on-its-face challenge based on supremacy clause arguments (which seem dubious in this case since the law assists the feds) it appears to me to be more grandstanding by the Obama administration. See the text of the law at the first link and commentary thereon at the second link LINK
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