Lowkey, 16, who only wanted to be identified by his nickname, poses for a portrait in Ferguson, Missouri July 24, 2015. [Photo/Agencies]

A year after rioters burned a convenience store and hurled rocks and gasoline bombs at police, who responded with teargas and rubber bullets, the Chosen for Change foundation founded by Brown's family is planning what it calls a weekend of "positive and peaceful" events.

Area law enforcement leaders say they also want a peaceful weekend and have been meeting with protest groups to discuss strategies to make sure that is the case, said Ferguson city spokesman Jeff Small. The Ferguson police force of 50 will be fully staffed this weekend and will have the help of the much larger St. Louis County police force, he said.

Ferguson's police came under heavy criticism for their militarized response to last August's protests, when they used heavy armored vehicles, dogs and noise cannons on crowds of protesters, at times escalating the violence in Ferguson's streets.

That response prompted US President Barack Obama in May to require US police departments to provide additional justification for using heavy equipment such as armored military-style vehicles and riot shields.