The lawyer for a Phoenix police officer who is challenging Arizona's new immigration law in court has asked a federal judge to merge his lawsuit with a challenge filed by the U.S. Department of Justice.

The officer's attorney, Stephen Montoya, tells U.S. District Judge Susan Bolton in a court filing that the cases are virtually identical because they claim the state law is trumped by federal immigration law and because both seek to keep the state law from being enforced.

The law requires police, while enforcing other laws, to question a person's immigration status if officers have a reasonable suspicion that the person is in the country illegally.

The seven challenges to the law are currently all separate lawsuits.