According to prosecutors, Stockley, who is white, shot Smith, who is black, five times following a car chase and then allegedly planted a gun in Smith's car following the shooting. The gun found in Smith's car later appeared to only have Stockley's DNA.
In the course of Friday's violence, St. Louis Police Chief Lawrence O'Toole said that at least 23 people had been arrested as of 6 p.m. on Friday, and 10 police officers had sustained injuries, including one officer with a dislocated shoulder and another officer with a possible broken jaw. A Missouri Highway Patrol trooper was also reported to have been injured.
The march, which began peacefully, turned violent after police officers used pepper spray on protesters who were blocking a bus police carrying additional cops to the scene.
In addition, an estimated 1,000 protesters went to St. Louis Mayor Lyda Krewson's house on Friday night, throwing rocks and breaking windows, according to the St. Louis Post-Dispatch. The mayor did not appear to be in, and some 200 police in full riot gear used tear gas to disperse the crowd.
In other locations, some marchers assaulted police officers with bricks and bottles, according to police reports, and law enforcement responded with tear gas and pepper-spray balls.
"Many of the demonstrators were peaceful. However, after dark, many agitators began to destroy property and assault police officers," O'Toole said in a video statement alongside Mayor Lyda Krewson.
"I would say that all in all today's protests were very peaceful and the police exercised great restraint," stated O'Toole, adding, "That is a good outcome for a very tense day."
According to KMOV-TV, Smith's mother, Anne Smith spoke on her son's death on Friday following the acquittal.
"I'm not going to stand here and say 'no justice, no peace.' My soul is burning, my heart is broken. I say I ain't got no justice, I could never be at peace," she said. "I can't speak for no one else, but I know the system didn't work on behalf of Anthony Lamar Smith."
Saturday's U2 concert in the midwestern US city was canceled after police asserted that they could not guarantee a full complement of security personnel at the event, as law enforcement employees would be required to work the city streets, instead of the concert.
On Saturday morning on the band's website, event promoter Live Nation and representatives of U2 released the following statement:
"We have been informed by the St. Louis Police Department that they are not in a position to provide the standard protection for our audience as would be expected for an event of this size. We have also been informed that local crowd security personnel would not be at full capacity."
"In light of this information, we cannot in good conscience risk our fans' safety by proceeding with tonight's concert. As much as we regret having to cancel, we feel it is the only acceptable course of action in the current environment."
Refunds have been made available to fans online or at the point of purchase.