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Justice Dept. warns Ala. sheriffs, police on immigration enforcement

The Justice Department has sent a letter to dozens of local law enforcement agencies in Alabama that receive federal money, warning them that they risk losing that funding if they're not careful in how they enforce Alabama's tough new immigration law.

The Obama administration has already sued the state, claiming the law is unconstitutional. Now it's keeping the pressure on by addressing how the law is carried out.

In an unusual letter, the assistant attorney general for civil rights writes to 156 Alabama sheriff's offices and police departments, telling them that the federal government is monitoring how they enforce the part of the law that requires checking the immigration status of people who are stopped for questioning.

It is critical, says Thomas Perez, that local law agencies "ensure that your enforcement of this law does not result in unlawful stopping, questioning, searching, detaining, or arresting" in violation of the Constitution "or targeting of racial and ethnic minorities."

Other states have passed similar laws, but they've been blocked by federal courts. The part of Alabama's law that requires checking immigration status, however, was allowed to go into effect by a federal judge.