Lizzie Stark and I have given a lot of thought to how demonstrations and protests will work at our Tipford event. What follows is some large-scale larp design nerdery.
The Tipford constraints are pretty severe -- protester players will outnumber authority NPCs by ten to one at least, maybe twenty to one at times, for example. It needs to be safe, and it needs to be both harrowing and dynamic and maybe even a little fun. People need to be able to engage at whatever level they are comfortable in the moment, from observing from a distance to a genuine Baldwin-Felts "oak towel rub-down" in the front lines.
We started out by chatting with Mohamad Rabah about the protest experience at Halat Hisar, and his advice was extremely valuable. The biggest take-away was to control the space -- the protest takes place in a confined corridor (in our case, a canal bridge) that is defined by clear physical boundaries. This will make up for the asymmetry in sides quite a lot.
There is a regular suite of safety tools that are always in play, and protests have special rules on top.
NPC Police and detectives (and, fingers crossed, their scabbin' PC allies) have slightly different rules (detectives can behave with savagery unavailable to the cops), but in general they can control the space by shouting orders, arresting people or clubbing people. Three cops touching you simultaneously with the intention to arrest means you need to leave the protest with them (in the full game being arrested is going to be some black box FUN). Getting clubbed allows you to choose whether you are injured (get to the rear, wear some bandage for the rest of the game), terrorized (run to the rear and collect yourself) or agonized (fall down and scream for a while). You can do each once during a protest if you want, or you can leave at any time. Detectives can also straight-up kill you, if that's what you want.
If you want to protest without any beating, you can carry a sign. Sign-carriers can be arrested but not struck. If you want to resist the police, sing! There's a secret ratio of singers-to-authorities, and as long as enough people are singing to satisfy the ratio, the authorities cannot act against you. You can't sing the same song twice, and the ratio gets harder and harder to meet the longer a protest goes on. Stop singing and they are going to roll you up. If you want to do battle with the cops, there are ways that emerge in play. It's a bad idea.
The authorities have one last tool -- they can call "disperse!" which is a metagame signal that the protest needs to end quite soon. When you hear it, you need to decide how you want your character to wind up in the aftermath of a violent crack-down that you are about to lose.
I expect to modify it as we learn more.