"NHTSA does not publish a star rating above 5," said Tesla in its original press release, "however safety levels better than 5 stars are captured in the overall Vehicle Safety Score (VSS) provided to manufacturers, where the Model S achieved a new combined record of 5.4 stars."
Tesla is saying they have the safest car--or at least have achieved the top NHTSA vehicle safety score ever--and that's not in line with NHTSA's guidelines.
Although derived from the same test data, VSS scores are not intended to be reported according to the NHTSA's 5-star scale, meaning that the automaker is making certain assumptions in order to project a combined 5.4-star rating. Tesla claims this score is the "best safety rating of any car ever tested," exceeding even all SUVs and minivans, and sets a "new NHTSA vehicle safety score record."
That's a no-no, according to NHTSA.
"NHTSA does not rate vehicles beyond 5 stars and does not rank or order vehicles within the star rating categories," explained NHTSA through a statement on the agency's website. The statement pointed to NHTSA's communication usage guidelines, which further stipulate that "NHTSA strongly discourages the use of potentially misleading words such as 'perfect,' 'safest,' 'flawless' or 'best in class' to describe the star rating received by the vehicle."
While none of the discouraged phrases are explicitly mentioned in Tesla's press release, the subtext is clear. Tesla is saying they have the safest car--or at least have achieved the top NHTSA vehicle safety score ever--and that's not in line with NHTSA's guidelines.
We reached out to Tesla for comment and the electric automaker says it stands by its press release.