Immigrant rights advocates are urging a federal appeals court to halt Arizona Gov. Jan Brewer's order denying driver's licenses for young immigrants who have gotten work permits and avoided deportation under an Obama administration policy.

In a 77-page brief filed Monday evening with the 9th U.S. Circuit Court of Appeals in San Francisco, the immigration rights advocates argue that Arizona's policy is unconstitutional because it is trumped by federal law.

Those affected are called "dreamers," after the proposed federal DREAM Act, which would grant legal status to those brought to the country illegally as children and who meet certain conditions, such as completing high school, attending college or serving in the military.

Advocates are seeking to overturn a May decision by U.S. District Judge David Campbell that denied a request for an order prohibiting the policy.

But Campbell also said immigrant rights advocates are likely to succeed in arguing that the state lets some immigrants with work permits get driver's licenses yet won't let immigrants protected under Obama's program have the same benefit.

President Barack Obama issued an executive order earlier this year that, in effect, does what the DREAM Act would do if passed by Congress. The order provides a two-year deportation deferral and allows issuance of work permits to "dreamers."

Following that, Brewer issued her own order banning those with deferred deportation from being issued state driver's licenses. She said under the law, they still are in the country illegally.