Earlier this year, federal vehicle safety regulators reached a voluntary agreement with nearly two dozen car manufacturers to make forward-collision warning and automatic emergency braking features standard in their cars starting in 2022. But some consumer safety advocates believe this is too long a wake and have gone to court in the hope of pressing the National Highway Traffic Safety Administration into taking more immediate action.

Consumer Watchdog, the Center for Auto Safety, and Public Citizen filed the lawsuit [PDF] in federal district court in Washington, D.C. Wednesday claiming NHTSA failed to respond to the groups’ formal request that the agency require automakers to adopt advanced safety technologies.

The groups sent NHTSA a petition [PDF] back on Jan. 16, asking the regulator to begin the rule-making process to require cars to use Automatic Emergency Braking (AEB).

AEB is composed of a set of three technologies that use combinations of radar, reflected laser light, and cameras to alert the driver of a likely collision and intervene if needed. Specifically, AEB can warn drivers that a forward collision is imminent, intervene when the driver does not respond to the warning, and apply supplemental braking when the driver’s braking is insufficient.

The groups contend that such features could prevent or limit the injuries and property damage sustained in nearly one million crashes each year.

According to the lawsuit, NHTSA failed to follow federal law in responding to the petition in a timely manner, and asked a court to require the agency respond to the request within 30 days.

Under federal law, NHTSA is required to grant or deny a petition within 120 days of receipt. That, the groups say, didn’t happen.

Instead, NHTSA — which estimates that such braking systems could save up to 110 lives a year — announced in March a voluntary agreement with carmakers to put AEB technology in almost all the cars they make starting with 2022. However, under the deal, manufacturers of manual transmission vehicles, and some heavier SUVS and trucks would have more time to equip cars with the safety features.

While the agreement was meant to placate concerns and get the ball rolling on such safety systems, Consumer Watchdog, the Center for Auto Safety, and Public Citizen claim the deal essentially allows manufacturers to “roll out weak versions of the technology on an unenforceable ‘voluntary’ basis.”

The groups contend that the voluntary agreement announced does not require that AEB become standard equipment in cars, and that carmakers who do not include the systems in vehicles by 2022 will face no repercussions.

“Voluntary standards don’t work,” Joan Claybrook, a former NHTSA administrator and president of Public Citizen, said in a statement. “They protect manufacturers, not consumers. AEB is one of the most important lifesaving automotive systems available today.”

Instead of responding to the petition and focusing on a timely issue that the groups believe could save lives, the groups say NHTSA has wasted time on initiatives and rule-making that won’t be necessary for years to come.

“This year, NHTSA devoted enormous agency resources to ‘driverless vehicles,’ which are years or even decades away, while a safety system that is ready to start saving lives right now has been relegated to the whims of the auto companies,” Harvey Rosenfield, Consumer Watchdog, said in a statement.

Claybrook brought up the possibility of an AEB lawsuit last March before a Consumer Federation of America panel on autonomous driving. She asked panelist and NHTSA Associate Administrator Nathaniel Beuse why the agency had allowed carmakers to establish the timeline themselves rather than issue a rule.

At the time, Beuse argued that the sometimes-lengthy federal rulemaking process — and the inevitable heavy lobbying and legal challenges that can result — would have likely taken as much, if not more, time than coming to the voluntary agreement with the industry.

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