Transportation Department is losing top auto safety regulator after a few months on the job

The Department of Transportation said on Friday that Steven Cliff, the head of the National Highway Traffic Safety Administration, plans to leave the agency in September after three months in the top job.

Ann Carlson, the chief counsel of NHTSA, will take over Cliff’s duties, U.S. Transportation Secretary Pete Buttigieg told CNBC in a statement.

Cliff, who became head of NHTSA in early June, is leaving to helm the California Air Resources Board, a climate agency focused on reducing air pollution in the state. CARB announced on Friday that Cliff was appointed as its next CEO, after Richard Corey, the prior CEO, retired at the end of June.

During his tenure with NHTSA, Cliff worked on new fuel economy standards, and new vehicle safety rules that are intended to increase safety for drivers, cyclists and pedestrians. As more advanced technologies have been adopted by automakers, the agency is increasingly dealing with concerns about the safety of electric vehicle batteries, and software that’s controlling cars.

Automotive safety activists, including Ralph Nader, have been calling on NHTSA to stop Tesla from testing unfinished driver assistance software with ordinary customers on public U.S. roads because of how frequently it malfunctions.

Cliff led the agency to issue a “standing general order,” which mandates that automakers provide NHTSA with data on fatal and other significant collisions that involved their cars and advanced driver assistance systems (ADAS), or more technologically sophisticated automated driving systems.

ADAS options available in consumer cars include Tesla’s Autopilot, Full Self-Driving and FSD Beta systems, Ford’s Blue Cruise and Cadillac’s SuperCruise. None of them make cars safe for use without an attentive human behind the wheel. Automated driving systems are featured in robotaxis being developed by Waymo, Cruise and others.

Cliff was nominated in October by President Joe Biden to lead the NHTSA after serving as deputy administrator since February 2021.

Secretary Buttigieg thanked Cliff for his service at the agency “and his work to protect the lives of the American people by strengthening the safety of motor vehicles and reducing their emissions.” 

NHTSA declined to share any further details about the circumstances of Cliff’s departure.

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