Joshua Munns, John Cote and John Young were working for Crescent Security Group in November 2006 when they and two other co-workers were ambushed and abducted while guarding a military convoy near the southern Iraq city of Safwan.
The complaint, which filed Monday in U.S. District Court in Sacramento, seeks punitive damages and challenges the constitutionality of the U.S. government's practice of using private military contractors in war but not supporting them when they are injured, killed or kidnapped.
"The primary goal is to peel back the lid on this black box .... to ask the hard question about what this
'War on Terror' is about," Bill Palmer, an attorney for the plaintiffs, told The Associated Press.
The State Department did not immediately respond to a request for comment.
Before they were killed, Munns, Cote and Young each had a finger cut off and were forced to eat glass. Their bodies weren't found until spring 2008, and their abductors have never been identified, according to the suit.
The families allege that State Department officials didn't keep them apprised about the kidnapping investigation and blocked their efforts to negotiate with the abductors. The suit claims the kidnappers were criminals looking for money, not terrorists.
Mark Munns of Anderson, Calif., told the Redding Record-Searchlight that the families filed suit in hopes of learning what federal officials know about the abduction and what steps they took to find his son and the other kidnapped contractors.
"We would like to get as close to truth as we can," Munns said.