Days of protests continue in St. Louis after a judge found police officer Jason Stockley not guilty in the 2011 death of Anthony Lamar Smith.

The protests follow a pattern seen since the August 2014 killing of Michael Brown in nearby Ferguson: The majority of demonstrators, though angry, are law-abiding. But as the night wears on, a subsection emerges, a different crowd more willing to confront police, sometimes to the point of clashes.

Protest organizer Anthony Bell said he understands why some act out: While change can come through peaceful protests, such as those led by Dr. Martin Luther King Jr., years of oppression has caused some to turn violent.

โ€œI do not say the (unruly) demonstrators are wrong, but I believe peaceful demonstrations are the best,โ€ Bell said.

Many protesters believe police provoked demonstrators by showing up in riot gear and armored vehicles; police said they had no choice but to protect themselves once protesters started throwing things at them.

Stockley shot Smith after high-speed chase as officers tried to arrest Smith and his partner in a suspected drug deal.

Stockley, 36, testified he felt endangered because he saw Smith holding a silver revolver when Smith backed his car toward the officers and sped away.

Prosecutors said Stockley planted a gun in Smithโ€™s car after the shooting. The officerโ€™s DNA was on the weapon but Smithโ€™s wasnโ€™t. Dashcam video from Stockleyโ€™s cruiser recorded him saying he was โ€œgoing to kill this (expletive).โ€ Less than a minute later, he shot Smith five times.

Stockleyโ€™s lawyer dismissed the comment as โ€œhuman emotionsโ€ during a dangerous pursuit. St. Louis Circuit Judge Timothy Wilson, who said prosecutors didnโ€™t prove beyond a reasonable doubt that Stockley murdered Smith, said the statement could be ambiguous.

Stockley left the police department and moved to Houston three years ago.