I don't want to sound like a homicidal maniac but I have never had a problem with the notion of shooting my way out of a rioting mob and have been forced to do just that twice to survive, once in Panama City, Panama and once again in Rio de Janero. I will state now that very little quiets the rampant lawlessness of a rioting crowd or mob willing to or having turned violent more than close in gunfire and blood in the eyes, especially if it belongs to the person who was just standing in front of you and women are not exempted; and like most mobs or rioting crowds, it stops them and they will not surge forward to further the attack (least not in my experience) when punkins start poppin' all around you and what makes them pop is steady and aimed.
I am from a very old school which says that I can control any mob with tear gas and any riot with one machinegun and I can tell you that those tactics work, although it is not considered 'pc' these days.
The fool who stands in front of a yelling mob and incites them to attack is the first fool to get shot and that usually makes the others back away, especially if they see you are resolute and willing to defend yourself by leaving more of them dead. This is not to flame, it is simple fact as I have seen it.
Mobs and rioting crowds adopt the attitude that young girl adopted because nobody who knows them can incriminate them - they feel all powerful. To the one who say 'what are you going to do' you send the first bullet. I will admit there is a place for double stack 9mms and carrying a extra magazine although I usually prefer the heavier calibers, but they both work.
I firmly believe that laws should allow for defensive shooting/self defense when confronted by a mob or rioting crowd as there is absolutely no guarantee that they will either let you alone or not stomp you to death just for being in their way and I agree with Conan that a bit of 'herd thinning' oft prevents further rioting occurances. jmtcw.