In CT, the M3W is registered as a motorcycle. No driver helmet required and only a passenger under 18 is required to wear one.
Just over a year ago Missouri passed a "Cycle Car" category for the trikes that do not fit traditional trike standards, such as a saddle to straddle and handlebars, not a steering wheel.
In this category you do not need a "M" endorsement on your driver's license, but still are required to wear a helmet. That's odd, but it's still a motorcycle sorts and in MO you have to wear a helmet to ride a 2 or 3 wheeler. With the advent of all the Polaris Slingshots being sold in the state, not many of the drivers had the "M" endorsement so a lot of lobbying went on and they got the law tweaked to the "Cycle Car".
