cartechboy writes "There's always that kid in the class that ruins it for everyone when being graded on a curve. At the moment, that kid is Tesla and Elon Musk. Tesla's been proudly claiming the Model S is one of the safest cars in the word despite the recent fire controversy. And while it may be just that, claiming it earned 5.4 stars from NHTSA isn't pleasing the safety agency as there is no such thing as a rating higher than five. While NHTSA already released a statement indirectly to Tesla saying it doesn't release ratings higher than 5, Tesla continued to promote this fictitious rating. Now NHTSA has updated its guidelines explicitly stating safety ratings are whole numbers only and that 5 stars is the maximum advertisers can claim. If advertisers and automakers decide to disregard these rules NHTSA is threatening removal from the program or referral to state authorities for appropriate action. Basically, hey Tesla, stop making false claims."