Arizona fights Obama challenge to immigration law

PHOENIX (Reuters) - Arizona on Tuesday urged a federal judge to reject the U.S. government's bid to quash its strict new immigration law, arguing the border state is acting within its powers.

The law takes effect on July 29. It requires state and local police to investigate the immigration status of anyone they reasonably suspect of being an illegal immigrant.

The Justice Department filed suit this month seeking to block Arizona's law, arguing it would undermine U.S. foreign policy and violate the U.S. Constitution -- charges rejected by state lawyers.

"Arizona merely seeks to assist with the enforcement of existing federal immigration laws in a constitutional manner," lawyers for Arizona Governor Jan Brewer said in documents filed with the court late on Tuesday.

"It is (the Obama administration) that is attempting to impose immigration policies and priorities that contravene and conflict with federal law and unambiguous congressional intent."

The Justice Department declined to comment on the challenge.

U.S. District Judge Susan Bolton will hear oral arguments on Thursday and could issue a preliminary injunction if she finds that ultimately the Obama administration would succeed in its quest to have the law struck down.

Immigration is a divisive issue in the United States, where an estimated 10.8 million illegal immigrants live and work.

The Republican-controlled Arizona Legislature passed the law in April to try to stem the flood of illegal immigrants and to cut down on drug trafficking and crime.

Opinion polls have shown the state law is supported by a majority of U.S. voters. In November, voters will cast ballots for local and congressional elections. Democrats are struggling to hold onto control of Congress.

In a statement, Brewer said she was "confident that the court will reject President Obama's attempt to prevent our state from protecting its citizens as a result of his failure to enforce federal immigration laws."

"My filing today makes clear that the federal government will suffer no harm if (the law) is implemented because the act requires only that Arizona's law enforcement officers act in accordance with their constitutional authority and congressionally established federal policy."

Arizona argued that the government failed to secure the border, that half of all illegal aliens in the United States entered through the state and that illegal immigrants who had committed crimes accounted for 17 percent of the state's prison population.

(Reporting by Tim Gaynor in Phoenix; Editing by Jeremy Pelofsky and Stacey Joyce)