But by spring of 2018, the NHTSA had copped to the number being off. The agency did not wholly evaluate the effectiveness of the technology in comparison to Teslas not using the featureusing, for example, air bag deployment as an inexact proxy for crash rates. (The airbags did not deploy in the 2018 Autopilot death.)Because Tesla does not release Autopilot or Full Self-Driving safety data to independent, third-party researchers, its difficult to tell exactly how safe the features are. (Independent crash tests by the NHTSA and other auto regulators have found that Tesla cars are very safe, but these dont evaluate driver assistance tech.) Researchers contrast this approach with the self-driving vehicle developer Waymo, which often publishes peer-reviewed papers on its technologys performance.Still, the unknown safety numbers did not prevent Musk from criticizing anyone who questioned Autopilots safety record. It's really incredibly irresponsible of any journalists with integrity to write an article that would lead people to believe that autonomy is less safe, he said in 2018, around the time the NHTSA figure publicly fell apart. Because people might actually turn it off, and then die.Number QuestionsMore recently, Tesla has continued to shift its Autopilot safety figures, leading to further questions about its methods. Without explanation, the automaker stopped putting out quarterly Autopilot safety reports in the fall of 2022. Then, in January 2023, it revised all of its safety numbers.Tesla said it had belatedly discovered that it had erroneously included in its crash numbers events where no airbags nor active restraints were deployed and that it had found that some events were counted more than once. Now, instead of dividing its crash rates into three categories, "Autopilot engaged, without Autopilot but with our active safety features, and without Autopilot and without our active safety features, it would report just two: with and without Autopilot. It applied those new categories, retroactively, to its old safety numbers and said it would use them going forward.That discrepancy allowed Goodall, the researcher, to peer more closely into the specifics of Teslas crash reporting. He noticed something in the data. He expected the without Autopilot number to just be an average of the two old without Auptilot categories. It wasnt. Instead, the new figure looked much more like the old without Autopilot and without our active safety features number. Thats weird, he thought. Its not easyor, according to studies that also include other car makes, commonfor drivers to turn off all their active safety features, which include lane departure and forward collision warnings and automatic emergency braking.Goodall calculated that even if Tesla drivers were going through the burdensome and complicated steps of turning off their EVs safety features, theyd need to drive way more miles than other Tesla drivers to create a sensible baseline. The upshot: Goodall wonders if Tesla is allegedly making its non-Autopilot crash rate look higher than it isand so the Autopilot crash rate allegedly looks much better by comparison.