Tasers are illegal in my state, except for police officers. 
I’ve never really understood this. I can walk around with a 7.62 rifle if I wanted to, but I can’t carry a stun gun?
That said, there is some definite training you’ll need if you carry a stun gun or taser, so that you know the limitations of your equipment. You should also consider getting tased and certified yourself, so that if you should ever have to use it, you can clearly articulate your training and experience with it.