The Arizona legislature modified their racist and unconstitutional immigration law earlier this month because they knew that the original law wouldn't hold up in Federal court. The move was made in anticipation of a mountain of lawsuits that would have likely made the legislation null and void in the Federal appeals courts.
The original law would have allowed (and in many cases required) police in Arizona to use an immigration check as the reason to make initial contact with an individual. Now the law states that officers can check immigration status as a consequence of some other violation of the law or some other contact, which could be just about anything. The provisions in the modification, for the most part, always existed. This is currently part of normal police practice across the country. Police officers already contact immigration authorities to report suspects who may be undocumented, when the issue comes up as a consequence of other violations of the law. So if that's the case, why have a law that codifies what is already the normal practice? Because that was not the original intent of the law. Arizona is trying to be slick with this move.
The changes will help the State defend against legal challenges, and will make the law tougher to kill in the courts. However, the law is still racist and unconstitutional. The law will still require some level of racial profiling. It still violates equal protection rights. It would still require a certain segment of the population to show proof of citizenship, while not requiring the same from others. The only way that this law could be constitutional, would be if everyone in Arizona were required to carry proof of citizenship and all were scrutinized equally. Gov. Brewer herself tried to claim that she didn't know what an immigrant looked like (in an attempt to blunt criticism.... and to try to show that the law would be applied to everyone....of course that's a lie. Of course this whole issue is about Mexicans). It is inherently racist...even with the changes....the changes only lessen the degree of the racism. The law also tries to trump Federal laws and Federal jurisdiction, another problem for Arizona as it tries to come up with a defense. Unfortunately those who want to challenge the law will have a steeper hill to climb.
The modifications were aimed at fixing some of the 4th amendment problems. But the problems with the 14th amendment are still there. Fortunately, this law was so horribly bad to begin with, that there are a number of routes to kill it. The modifications only plug one hole in the dam. This is why I believe the law was never really meant to be practical. I think it had more to do with Arizona wanting to send a message to Washington.
Read the Text of the Actual Law with the Modifications