I do not have any electric vehicle so I do not know the rule. However, I often see a sticker on the back of the tesla vehicle because I heard that you need that to use the carpool lane. Why would you need to have that sticker? Would people already know that a Tesla is full electric and not a hybrid. So should the Tesla not need that sticker? I ask this because I do not want to use that sticker on my 2020 Roadster. The sticker just make the car look cheap and make it less pleasant looking. There is no way that I will put that sticker on my 2020 Roadster. I rather not use the carpool lane.