When is a vehicle not a "vehicle"?

I wonder if 1L's are still subjected to the old hypothetical invented for their sheer torment. You're in Central Park with a child in a stroller. A sign says, "No vehicles permitted in the park." Are you in trouble? The answer: it depends, of course. If you're a strict constructionist, yes. Your child is on wheels. But if you are permitted to ask what the purpose of the rule is--is it to reduce the risk of serious injury, of noise and annoyance, of pollution--then it's probably no. Now, what about a motor scooter? a motorized wheelchair? If you're a 1L, the very question means that whatever you thought you knew, you now know you don't. (The uncertainty principle applies to the law too.)

Here I am again, 20 years later. Is a Segway a "vehicle" or not? Steven Waters told the Town Council tonight that an aggressive campaign on Segway's part got the laws in 41 states, I believe he said, to say that a Segway is not a vehicle. It is, rather, an "electric personal assistive mobility device." Ergo it needs no headlights. By now, at least, I think I know a policy issue when I see one.