In a sign of growing opposition to President Obama's immigration policy, Iowa has become the latest state to deny driver's licenses to young illegal immigrants who receive deferments from deportation.

Iowa joins Michigan, Nebraska and Arizona in denying licenses or non-operator identification cards because, officials say, Obama's deferred action program doesn't grant legal status in the United States. Officials in each state cite laws restricting the licenses to foreigners who reside here legally.

The program, which began in August, offers a renewable two-year reprieve for qualified young people who were brought to the United States as children. Recipients also gain permission to work here legally. So far, more than 355,000 applicants have been accepted and nearly 103,000 have been approved, according to the latest government figures.

Iowa's Department of Transportation Director Paul Trombino III said in a statement:

"The Iowa DOT understands the exercising of this prosecutorial discretion by the U.S. Department of Homeland Security does not grant lawful status or a lawful immigration path to persons granted Deferred Action for Childhood Arrivals status. Rather, it is prosecutorial discretion extended in a blanket fashion to persons who are not lawfully authorized to be present in the United States."

Republicans have criticized the program as backdoor amnesty designed to boost Latino support for Obama. The four states denying licenses are led by Republican governors. One of them, Nebraska's Dave Heineman, has pledged to deny not only licenses, but welfare benefits and other services to illegal immigrants, unless required by state law.

Washington and New Mexico are among states that issue driver's licenses to illegal immigrants, although New Mexico Gov. Susana Martinez, who is a Republican, wants her state's enabling law repealed. Illinois could be next to issue licenses after the state Senate recently approved a bill.

At issue is whether the federal program's authorization to stay and work here legally also confers temporary legalized status.

Iowa officials cite the memorandum issued by Homeland Security Secretary Janet Napolitano that outlines the new policy: "This memorandum confers no substantive right, immigration status or pathway to citizenship."

Immigrant advocates say people in deferred action status qualify for licenses under the 2005 Real ID Act, which they have used to file lawsuits to overturn the bans in Arizona and Michigan.

The Real ID law, an anti-terrorism measure aimed at creating a national driver's license system, lists people in deferred action status among the authorized noncitizens who are eligible to obtain a temporary license.

Immigrant advocates also say the states are encroaching on the federal government's authority to set immigration policy, a separation reinforced by the Supreme Court ruling this year that severely weakened Arizona's immigration enforcement law.

"Deferred action has existed for decades and decades. It is a form of lawful presence, just like other forms of administrative relief under our immigration laws," says Thomas Saenz, president and general counsel of the Mexican American Legal Defense and Educational Fund, which is one of the groups suing in Arizona.

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