The head of the US National Highway Traffic Safety Administration (NHTSA), Jonathan Morrison, has written to autonomous vehicle developers warning of an "unacceptable" pattern of driverless cars interfering with police, ambulance and fire crews. Describing the letter as a "call to action", he said such vehicles pose "a danger to the general public" and directed companies to fix the problem immediately, adding that the agency would meet each developer by the end of July and could use its enforcement powers against those that fail to act.

Morrison said NHTSA had documented a "clear pattern" over recent months of vehicles driving into active emergency scenes, blocking ambulances and firefighters, and failing to respond to flashing lights, fire and traffic cones. City officials have complained that Waymo robotaxis impede emergency responses — a San Francisco fire chief said the cars frequently block station access, while an Austin case saw a Waymo block an ambulance for two minutes during a mass shooting that killed three people and injured at least 14. Waymo declined to comment, while Zoox said it supported NHTSA's push for accountability. The agency has issued several past recalls over AV behaviour, yet its release also promoted the Trump administration's moves to ease rules on deploying vehicles without steering wheels or driver-operated brakes.