WATCH: Tesla Driver Joshua Brown Filmed Himself Driving Without Hands

Former Navy man Joshua Brown, a technology company owner from Ohio, became the country’s first fatality in a self-driving car. A new witness report says that Brown may have been watching a Harry Potter video when the autopilot failed to apply the brakes for a turning tractor trailer, thinking its white side was the sun. The crash occurred May 7 in Florida, the New York Times says.

Brown had a YouTube channel in which he had posted videos of himself in the Tesla.

“The car’s doing it all itself… it takes all the stress out of it,” Brown, 40, says on one video, at one point laughing.

In another video, he writes about avoiding a crash: “Tesla Model S autopilot saved the car autonomously from a side collision from a boom lift truck. I was driving down the interstate and you can see the boom lift truck in question on the left side of the screen on a joining interstate road. Once the roads merged, the truck tried to get to the exit ramp on the right and never saw my Tesla. I actually wasn’t watching that direction and Tessy (the name of my car) was on duty with autopilot engaged. I became aware of the danger when Tessy alerted me with the ‘immediately take over’ warning chime and the car swerving to the right to avoid the side collision.”

He wrote that there was a “little bit of a blip in the steering” when he took over. “Tessy had already moved to the right to avoid the collision. I was not able to slow down even more due to the heavy traffic (cars were behind me). Once I got behind him I slowly added more room between us until he exited. I was not tail gating after the incident….Tessy did great… I am VERY impressed.”

Tessy was the name that Brown gave to his self-driving car.

He posted other videos on the channel too. One shows the car navigating in highway traffic.