Serious question. There is no field preemption or conflict preemption here. What is the government’s constitutional argument?
"Q Thanks, Robert. First I’m going to put aside what you said about being a Dallas fan. I’m just going to pretend that didn't happen. (Laughter.) On another more important topic, one thing as you have mentioned several times today, the President directed Justice to look at the Arizona law because he doesn’t want a patchwork of state and local laws. But right now there are dozens of so-called sanctuary cities that have their own policies that might potentially conflict with federal law, something that's led Governor Brewer to say that if Arizona is in violation of federal law, then so are these localities. So my question is, why did the President only ask DOJ to look at Arizona and not everywhere?
MR. GIBBS: Yes, well, let me see if I can get -- I don't know the answer to that, but I will try to seek some answer on that."