Tesla could not be immediately reached for comment on Thune’s letter.
The accident is the first known fatality in just over 130 million miles where Autopilot was activated, in contrast to a fatality every 94 million miles among all vehicles in the U.S., according to Tesla.
On Thursday, Musk tweeted that another crash involving a Tesla in Pennsylvania would not have happened if Autopilot had been turned on. "Onboard vehicle logs show Autopilot was turned off in Pennsylvania crash. Moreover, crash would not have occurred if it was on," Musk wrote.
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