<human>: Could you distill the essence of the text into 1-3 sentences?

I was browsing r/gaming, and I stumbled accross [This post] It shows a guy in a full gas mask, carrying a tear gas canister in prep to throw it back to the police. I've watched numerous videos of the confrontations between the police at the OWS, OccOak, OUCD, and other cities, and the protestors themselves. I've seen the tear gas that they fire, and the dispersal effect that that has on the crowds. 

My question: If some of the protestors at the aforementioned protests were to don the neccessary protective gear(like the man in the picture) and assume the responsibility of 'returning' the tear gas canisters to their owners in blue, what would happen? My first thought is that this would be considered assault, or something severe enough to require the police to heal the protestors with their magic wellness sticks, but I could be wrong.
<bot>: What would be the end result if protestors in the U.S. gave the police their tear gas canisters back, peacefully and in an organized fashion?