What's wrong with SB 1070?
Well, my main concern is with the "reasonable suspicion" clause. That strikes me as horribly vague. Some people think that when they see a lower-class Hispanic-looking person who speaks Spanish much better than English, then we can reasonably suspect that they are illegal immigrants. We already have a county Sheriff who goes fishing for illegal immigrants.
In our state, most illegals are Hispanics, but most Hispanics are not illegals. If you define your conception of what it takes to have reasonable suspicion, and on my blog I made an un-remarked-upon recommendation that we have reasonable suspicion just in case we have objective criteria leading to the conclusion that it is more likely than not that the person is illegal, then you could at least eliminate the worst of the profiling problems. You can't just stop a Hispanic and make an immigration status inquiry, because being Hispanic is not sufficient for it to be more than 50% likely that the person is here illegally.
It isn't just a racial issue; most illegal immigrants make less money than people here legally, and they are more likely to be monolingual Spanish speakers or poor English speakers than their legal counterparts. But if these criteria are going to be sufficient to justify and immigration inquiry then, since such in inquiry is considerably discommoding to its object, it runs afoul of a basic conviction that law-abiding citizens should not be treated differently by the government because of race, color, or national origin.
If these criteria are not sufficient, then I have doubts as to whether the law will actually get much of anybody deported. So my "fifty per cent solution" may result in the law not result in invidious profiling, but it might also render the law ineffective.