anything is a weapon in the eyes/mouth of a cop w/ a chip on their shoulder.
honestly, I'm fairly certain as long as the intended or manufactured purpose of the device is not to harm someone, you have a pretty good alibi/ defense, but people get fucked for shit.
I remember once me and my friends were fencing with shinai in a parking lot and all the sudden out of the blue 6 cop cars rolled up, lights on, 40mph, and they leapt out with guns drawn. They thought we had swords. Such a fucking scene.