nah there are many ways to limit police. Filming them is the obvious one, in more or less everyone's power in the West. If it were ineffective, why do they react so negatively to it in so many cases?
But I do "tech"nically agree with tec... passing laws is a questionable way to fix problems. If someone does submit a bill, you can sometimes use it as an opportunity to generate debate. Or, in our case, remind people that there is a liberty struggle going on in new hampshire and that they are invited to move here and join it.
I agree there that bringing their actions out into the light is probably actually one of the most effective ways to limit their abuse. The problem is not everyone is as brave or well informed in their rights as you are. Also I imagine in your locality you have built up quite a reputation among most of the local PD forces, and they know better than to try to cut corners in your presence. In a lot of peoples cases it ends with a "that's illegal", a phone snatch, and a delete button, and maybe an arrest. Though, none of this is an excuse not to try... just be aware of what you may be in for.