"Legal observers exist to help vindicate the First Amendment rights of the assembled. According to the National Lawyers Guild, which formalized the practice..."

"... such observers 'create documentation during events which can later be use (sic) in defense cases, public statements, and litigation which aims to hold law enforcement agencies accountable for the actions of their officers.' The Guild notes that legal observation has its roots in the Black Panthers’ 'cop watch' activities of the late 1960s.... In 1968, in connection with anti-war and racial justice demonstrations in New York City, the Guild 'took components from this practice' of cop watch to develop its legal observer program – the self-described 'eyes and ears' of a larger infrastructure of 'arrest hotlines, jail support teams, community bail funds ... attorney referral networks, and more.' Those who have adopted the Guild’s practice, such as the Minnesota ICE Watch group with which Renee] Good was reportedly affiliated, have advocated for activities that blur the line between observation and participation in protests...."

Writes Benjamin Weingarten in "The Grey Zone: When Do Protest Observers Become Lawbreaking Participants?" (Real Clear Investigations).