according to an article in a magazine this year..
30-40 percent of all people are born with a genetic issue that makes them immune to pepper spray.
anyone can build up a tolerance to pepper spray by adjusting their diet.
so basically right off the bat, pepper spray becomes useless on at least 30-40 percent of the population. and the rest of us have different resistance to it depending on how much chilli pepper weeat everyday.
and at the same time, drugs and booze, and medical conditions make the effects of pepper spray different on everyone. same goes forelectrical devices.
its somewhat hard to be born with any resistance to lead.