The United States constitution does give every American the right to peaceably assemble. I am cool as hell with that even though I might not agree with their cause ( which is within my rights). They do not and are not protected by the First Amendment when they throw Rocks, bottles or anything that within reason can cause bodily harm.
When they set fire or vandalize anything that does not belong to them. Anything other than non-violent chants is to be considered unprotected speech. Setting a limo on fire does not help your case but shows what kind of Animals you really are. Throwing stuff at Police shows that you have not evolved from an Animal.
Chanting Police should Fry like bacon should be classified as hate speech. You Liberal Criminals think that the laws don’t apply to them.