In a letter addressed to NHTSA Administrator Jonathan Morrison, the senators questioned the validity of Tesla’s core marketing figures, specifically the claim that its vehicles are ten times safer than those operated by humans. The lawmakers contend that such assertions lack transparent evidentiary support and demand that the agency scrutinize how these performance metrics are calculated. Beyond the immediate inquiry, the senators urged the National Highway Traffic Safety Administration to mandate stricter data reporting standards for all companies operating autonomous fleets.

This push for oversight coincides with an ongoing federal probe into Tesla’s driver-assistance software, which was escalated earlier this year following reports of multiple collisions and at least one fatality. As Tesla, Alphabet’s Waymo, and various autonomous startups continue to expand their presence on American roads, the debate over how to measure and verify the safety of self-driving technology has moved to the center of the legislative agenda.