In my "nanny" state of Washington it is licensed as a motorcycle and you need a helmet.
Sorry -- not so. In Washington state, if a three-wheeler has a steering wheel and seat belts, you do not need to wear a helmet. Take off your belts, and you need to wear a helmet.
Department of Licensing says that you need two people in the car to use HOV lanes (unless the three-wheeler is tandem seating). However, a guy I know with a 2012 M3W knows the head of the highway patrol and is looking into the actual enforcement. Will update when I can confirm.
