As I understand it, the reason for the blocking this is that it was congress that specifically made immigration status flexible. So if your visa expires but you are here because your country is in a situation similar to that of Libya or Haiti then the government offers you a temporary stay, the federal government doesn't issue a document that proves you are here under their auspices during that time. There are many different examples of these situations and each one has nuanced solution. Immigration status is not always black and white. There is no way for a state government to check that without violating civil liberties.