A preliminary investigation by the National Transportation Safety Board (NTSB) has confirmed that the driver of a Tesla Model 3 manually overrode the vehicle's Full Self-Driving (Supervised) system in a fatal crash that killed Martha Avila in her Texas home. The driver, Michael Butler, pressed the accelerator to 100 percent, disabling the FSD system. The vehicle was traveling at a speed greater than 70 mph when the crash occurred.

This finding aligns with statements made by Tesla AI head Ashok Elluswamy in June. Butler reportedly stated he was completing a DoorDash delivery and engaged FSD while changing music, after which he claims he passed out. Authorities found no alcohol or blood in his system, and the brake pedal was not applied in the moments leading up to the crash.

Avila's family has filed a wrongful death lawsuit against Butler and Tesla, alleging negligence. Butler has been charged with manslaughter. The National Highway Traffic Safety Administration (NHTSA) is also investigating the crash and previously opened a broader inquiry into Tesla's self-driving technology in October 2025.