Nine states, including Virginia, have filed legal briefs in support of Arizona’s new immigration law, arguing that they have preexisting constitutional authority to enforce federal immigration laws within their borders. The filings add political gunpowder to a tense legal showdown between Arizona State officials and the U.S. Department of Justice, which has filed a lawsuit to stop the Arizona law from going into effect July 29.

The public overwhelming supports the Arizona law, which requires police officers to inquire about legal presence if they have a “reasonable suspicion” that people they’ve stopped for another offense are in the country unlawfully.

Even some Democratic governors questioned the Obama administration’s strategy at a private White House meeting last weekend. “Universally the governors are saying ‘We’ve got to talk about jobs,’ ” said Gov. Phil Bredesen, D-Tenn. “And all of a sudden we have immigration going on.”

The amicus briefs point out that federal law already allows states to enforce immigration statutes. “While much of border enforcement is left to the federal government, federal law expressly allows states to arrest people who are not legally present in the United States.  Arizona’s law doesn’t change any of this.  That’s why we are stunned that the government has sued Arizona,” Virginia Attorney General Ken Cuccinelli said.

Virginia is one of two states that has implemented the federal Secure Communities program statewide. The automated program uses biometric information sharing to allow Immigration and Customs Enforcement agents to identify any illegal alien arrested by local law enforcement. The program is currently in use in 336 jurisdictions in 22 states and has been credited with the deportation of more than 8,500 criminal aliens convicted of murder, rape and kidnapping and more than 22,500 convicted of lesser crimes.

Michigan State Attorney General Mike Cox, a Republican who is running for governor, said “it is appalling to see President Obama use taxpayer dollars to stop a state’s efforts to protect its own borders.”

Virginia and Michigan were joined by Alabama, Florida, Nebraska, Pennsylvania, South Carolina, South Dakota, Texas, and the Northern Mariana Islands.