Updated

A suburban Virginia county has filed suit against the Department of Homeland Security in a bid to obtain information about an illegal immigrant who last August was charged with killing a nun in an alleged drunken-driving crash.

The department so far has refused to provide Prince William County officials with documents pertaining to suspect Carlos Martinelly-Montano, after the county made a formal request last year. The department claims it cannot hand out that information because it has to adhere to the U.S. Immigration and Customs Enforcement, or ICE, privacy policy.

But Board of County Supervisors Chairman Corey Stewart and the rest of the council now wants to compel the department to provide the data, filing suit in federal court. The suspect had a prior drunken-driving record and was turned over to ICE before the crash, so county officials want to know why he hadn't been deported.

"The federal government did not uphold its responsibility to protect its citizens. Now they have the audacity to ignore a request of information that Prince William County has every right to," Stewart said in a written statement. "This lawsuit was a last resort and is a result of the federal government's lack of cooperation and arrogance."

The lawsuit urges the Department of Homeland Security to provide a report on why Montano was originally released from custody, as well as a record of contact between the department and the suspect.

The county is meanwhile preparing to potentially file suit over a separate immigration-related request. The county is trying to get detailed information on the 3,000 illegal immigrants handed over to ICE since the county started enforcing immigration law in 2008 under a joint local-federal program.

The department provided some information, but Stewart was not satisfied.

The latest push for the documents comes in the wake of a killing spree that took place in Manassas, Va., last month, leaving three dead and three wounded. Jose Reyes-Alfaro, an illegal immigrant originally from El Salvador who was previously held in federal custody awaiting deportation, was charged in that case.

It marked the second time in six months an illegal immigrant with a prior record was charged in Prince William County in connection with a deadly crime.