On his Monday show, conservative radio host Mark Levin explained why yesterday’s Supreme Court ruling on SB 1070, the controversial Arizona immigration law, could pave the way for legal action against “sanctuary” areas that welcome undocumented immigrants.

Levin, the author of “Ameritopia: The Unmaking of America,” first expressed his disappointment in Chief Justice John Roberts for signing on with the decision, which dismantled much of the Arizona law while upholding a section that allows law enforcement to force suspected immigrants to show documentation that proves their legal residency.

“I must tell you that the decision is bizarre,” he said. “It’s not incomprehensible, but it is largely incoherent. I’m extremely disappointed in the chief justice for signing on with this. There is no deal, no reason for him to jump on that side. It was 8-0 on the issue of stopping and checking for documentation in the course of an investigation for possible criminal activity.”

However, Levin said, if states can no longer set policies dealing with someone’s immigration status, then sanctuary cities or states may find themselves in hot water.

“If this case stands for the point that only the federal government has power in the area of immigration, then let me suggest that sanctuary cities and sanctuary states are unconstitutional because they exist to defy federal immigration law,” Levin said. “That’s number one. So folks out there that have standing, sue your cities, sue your states if they have declared themselves to be sanctuary cities or states because they do not have the constitutional authority to declare butkus. So turn this law against them.”

The same goes for states that offer in-state tuition at colleges for illegal aliens, Levin said.

“In-state tuition clearly is unconstitutional because Congress has not authorized it for illegal aliens,” he said. “Again — if the court’s position is that the federal government has complete preemptive authority over this issue, the federal government has not authorized in-state tuition for illegal aliens of any kind. So sue your state if they’ve instituted in-state tuition for illegals.”

This point has been made by Levin’s Landmark Legal Foundation in a brief published earlier this year, noting a decision similar to the one yesterday would create “chaos and confusion”:

If the federal government’s politically motivated challenge of SB 1070 is successful, rather than bring consistency and certainty to immigration on a national level, it will create even more chaos and confusion. The federal Executive Branch’s selective and inconsistent application of field preemption in immigration law must not be given this Court’s imprimatur. Otherwise, lawless state and local governments that have adopted sanctuary policies that directly violate federal immigration law and have not been challenged by the Executive Branch will continue to be lawless. Conversely, law-abiding governments that help enforce federal immigration law will be without direction.

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