What states are Suicide knobs (AKA Brondie knobs, Spinners, Granny knobs .ect) legal?

I thought they were illegal in all states, except when the driver had a disability. The best way of finding out is to call your local DMV (or DoT or whatever it’s called in NH) and find out.

I’ve seen them on cars here in MO, in conjunction with other after-market apparata that would permit a person (typically one without the ready use of his legs) to operate a car with his hands. It is my suspicion that one would require a doctor’s note in a city/state filing cabinet in order to attach one.
It’s an interesting experience, working a lever connected to the gas and brakes. You don’t have the right muscle memory for it, so all of your actions have to be deliberate.