Court documents filed Monday allege that five auto companies were aware of defects that caused Takata air bags to potentially harm or kill motorists but continued to use them anyway to save on costs.

The documents claim that Honda, Ford, BMW, Toyota and Nissan have known about the issues with the Japanese manufacturer’s air bags for more than a decade but still used them because Takata was cheaper than its competitors and could produce the bulk quantities the automakers needed, according to the court documents.

The new allegations come as Takata entered a guilty plea Monday as part of an agreement with the Department of Justice to resolve the agency’s investigation into the matter. That deal, reached last month in the final days of the Obama administration, required the company to pay $1 billion in fines and restitution to automakers and victims. In December, three Takata executives were indicted on wire fraud charges, also as part of that investigation.

Monday’s allegations are the latest in a civil lawsuit initially filed in 2015 against Takata and seven carmakers by attorneys representing people injured by the faulty airbags. They raise new questions about who should shoulder blame for the 11 deaths and 180 injuries the air bags have caused in the United States, according to the National Highway Traffic Safety Administration, as well as others around the globe.

Takata admitted to the Justice Department last month that its employees deliberately omitted and falsified data to make its air bags appear safer, then passed the doctored information on to automakers. Car companies pointed to that confession last week as a reason why they should be exonerated from any liability in the civil lawsuit.

But attorneys representing the victims say automakers had independent information that the air bags were faulty and chose to continue installing them in millions of vehicles, according to Monday’s filing.

“For the automotive defendants to call themselves victims insults the real victims here — hundreds of people who have been seriously injured or killed by a device that was supposed to protect them, and tens of millions of vehicle owners who have been forced to bear the risk of such injury and incurred substantial economic damages,” the documents say.

Toyota and Ford declined to comment on the accusations. Nissan and BMW did not immediately return requests for comment.

The lawyers allege that Honda was “intimately involved” with the design of Takata’s air bags and that at least two air-bag inflaters ruptured during testing at Honda’s facilities in 1999 and 2000. Honda used the air bags anyway, according to the court documents, and at least 77 air bags ruptured on the road before the company implemented a nationwide recall.

Honda called the allegations that it used the air bags despite safety concerns “categorically false” and pointed to the Takata settlement as evidence that automakers were misled to believe the product met safety standards.

“The reality is that when Honda learned of the risks that these air bag inflaters presented, Honda reacted promptly and appropriately by issuing safety recalls and replacing the affected Takata air bag inflaters at no charge to its customers,” the company said in a statement.

Takata also filed its own court update in the civil case Monday following its guilty plea in the Justice Department investigation.

The company said its agreement with the agency should have “limited (if any) impact” on the pending civil litigation, because it does not address Takata’s liability in the particular case. Although Takata admitted to providing automakers with false safety information, the company’s agreement “does not state that this conduct caused the field ruptures and recalls, or the alleged economic harm resulting therefrom,” the company’s filing said.

Alice Crites contributed to this report. 

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