On November 7, 2016, an unnamed police officer, referred to as “John Doe,” sued Deray Mckesson for injuries the officer sustained when an unidentified third party—not Mckesson—threw a “rock-like” object during the protest and hit him. The officer sued Mckesson, not the third party, on the theory that Mckesson “should have known” that the protest “would become violent as other similar riots had become violent.” He did not claim that Mckesson authorized or even knew of the rock-throwing. Indeed, to this day the rock thrower remains unidentified.
https://www.aclu.org/cases/doe-v-mckesson