The Transportation Security Administration was sued on Wednesday by a group that says the agency responsible for screening people at airports deployed body scanners without following the required rulemaking process.

The Competitive Enterprise Institute filed the lawsuit in an effort to force TSA to follow a court decision that said the agency never allowed for public comment on its new plan to screen people before they board their flights.

CEI noted that in 2011, a federal appeals court found that TSA was required to develop its body scan regulation under a federal law that requires public comment and other transparency measures.

While TSA has said it would comply with that decision, it has yet to issue any final rule on scanners, even though it continues to use them.

"For four years the TSA has flouted the court's order, preventing the public and outside experts from scrutinizing their actions as required under the law," said Marc Scribner, a CEI fellow and co-petitioner in the suit. "This lawsuit aims to enforce that court decision and bring much needed accountability to an agency plagued by lawlessness."

Scribner added that a leaked report on efforts to judge how well TSA is doing showed that TSA failed to find fake weapons that people tried smuggle onto flights 96 percent of the time. He said that calls into question whether the scanners are working at all.

Meanwhile, scanners that are in place in violation of the court order are posing privacy issues for travelers. The National Center for Transgender Equality, a co-petitioner in the suit, said the scanners are "a cost to travelers' privacy."

CEI's suit asks the Washington, D.C., Circuit Court of Appeals to enforce its 2011 decision that said TSA was in violation of federal law because of the way it developed the rule. It also asks the court to "force the TSA to produce its required final rule on body scanners within 90 days."