Black Friday Protests

Because of another recent incident of police brutality against an African American, this time in Chicago, people are outraged. Although there were protests and mobs earlier this past week, the biggest protest happened on Friday, the 27th of November, also known as Black Friday because of the Holiday shopping that takes place after Thanksgiving.
               These organized protests took place around some of the busiest shopping areas of Chicago. They included group chants, human barriers, and a few violent exchanges, requiring police intervention. About the violence, Parrett, a protester, said “If we get hurt, you gotta hurt too.” (USA Today).
               The protesters (and others) are petitioning for the mayor, county prosecutor, and police superintendent to be fired and for an investigation into the Justice department.

Questions:
Do you think that violent protests are allowable in this case?
Is vengeance justified even if the victims of revenge were not the perpetrators of the original sin?
Should the mayor, county prosecutor, and police superintendent be fired?

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