The NHTSA has laid down the law about how to interpret their results.
There's no doubt that the Model 3 is a very safe car, it achieved the highest possible five-star rating from the National Highway Traffic Safety Administration (NHTSA) in all categories. However, Tesla's claim that it is the safest car ever tested may not be quite as clear-cut.
According to a statement issued by the NHTSA, it specified that its crash tests combine into an overall safety rating and it does not rank vehicles that score the same ratings. They did not happen to single out Tesla, but the statement did come out only days after Tesla had released a blog claiming that the Model 3 achieved the lowest probability of injury of any vehicle ever tested by the NHTSA.
The data quoted by Tesla as posted on its website has been gleaned from the NHTSA injury data stats that it compiles each year. According to those figures the top three spots are clearly occupied by the Model 3, S and X.
There are also videos comparing the crash performance of the Model 3 to a number of similarly sized sedans, however drawing a definitive conclusion from these without having in-depth knowledge of the testing procedures is unlikely to be very accurate. Aside from the Model 3, there have been a number of five-star rated cars this year, including the Toyota Camry, Ford Mustang and the Honda Accord.
The statement went further by saying that the NHTSA does not distinguish safety performance beyond a five-star rating there is no 'safest' vehicle among those vehicles achieving the highest measured results. It also warned about using terms such as 'perfect' to describe the overall score.
It seems then that Tesla has applied their own interpretation to the NHTSA testing procedures. In Tesla's defence though, there is clearly a grey area that the NHTSA needs to shed some light on. Its ratings may only go to a five-star level, but it is quite logical to assume that not every car with this rating will have performed identically across the board. Its own data alludes to this very fact.