Oh, "it happens." But you won't say that about the girl accidentally kidnapped in Phoenix, not by illegal migrant workers at that. Double standards.
Why do you think the mayor of Phoenix strongly opposes Arizona's new immigration law?
The point is that crime rate declining in Arizona is a fact. Illegal immigration increasing in Arizona is a fact. When people say that illegal migrant workers bring with them a wave of all sorts of serious crimes are simply lying.
How do you know it wasn't done by illegal migrant workers? What's to say they're not also working for the cartels or moonlighting as drug dealers? The drug pushers actively recruit illegals to do their dirty work.

You keep circling around this crime declining bit. It doesn't mean anything as long you can't prove that the number of crimes committed by illegals has decreased. Saying crime has decreased overall doesn't mean anything when the number of illegals committing crimes may have increased. Not providing statistics on that isn't helping your argument.
Why is it that American citizens are expected to live in constant fear of kidnapping and other crimes because the perceived rights of illegal immigrants may be violated? Why are Americans second class citizens in their own country?