Former St. Louis Metropolitan Police Officer Jason Stockley was found not guilty of murder on Friday by a judge's ruling after a bench trial in early August.

Stockley was charged with first-degree murder and armed criminal action in May 2016, about 4 1/2 years after shooting and killing Anthony Lamar Smith Dec. 11, 2011. Stockley opted for a bench trial, which was overseen by veteran Circuit Judge Timothy Wilson Aug. 1 through Aug. 9. On Friday, Wilson made his decision, finding Stockley not guilty on both counts.

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Al Watkins, attorney for Smith’s fiancée and daughter, says the family is devastated and appalled by the judge’s ruling. Watkins says he and the family take particular issue with a statement in the ruling they consider to be prejudicial:

“Finally, the Court observes, based on its nearly thirty years on the bench, that an urban heroin dealer not in possession of a firearm would be an anomaly.”

“We all know what ‘urban’ means. Urban means ‘black.’ I find that to be offensive. I find that to be demonstrative of a judge who thinks that those who are reading this verdicts are morons,” said Watkins.

Watkins says his clients are calling for peaceful protests.

After the decision was announced protesters started to gather at Market Street and Tucker Boulevard, near the civil courts building downtown. Michael Brown Sr. was near protesters downtown and told Ryan Dean the ruling brings back emotions from his son’s case.

“I would definitely tell them not to never give up, you know, stay with faith, and hopefully something else could change. That’s what I’ve been banking on right there for myself. They’re just words of encouragement that keep me still moving and fighting for what I believe is right,” said Brown Sr.

The group of protesters grew to a few hundreds, and they moved to the ramp to get onto I-64 at Clark Street, but St. Louis police officers with bicycles gathered to prevent them from impeding highway traffic. As of 10:30 a.m., the protests have remained peaceful.

Police say as of 12:15 p.m. only one protester has been arrested. The person was taken into custody around 11 a.m. at Washington Ave. and 14th Street for damaging a police vehicle.

PHOTOS | Protests in downtown St. Louis after Stockley decision

Circuit Attorney Kimberly Gardner held a news conference and expressed her disappointment in the judge’s decision because she feels her office presented sufficient evidence of guilt. Despite the ruling, Gardner says nothing will stop her from continuing to provide every person with a fair and impartial legal process.

“This verdict will not stop me,” said Gardner. She also called for protests to remain peaceful. “Destruction of our community is not the answer.”

The original incident report said Stockley and his partner saw what they believed to be a drug deal behind the Church's Chicken along Riverview Boulevard. When Stockley approached, one of the men ran off and Smith fled in his car.

According to the probable cause statement, Stockley shot at Smith's car before pursuing him in a car chase. Stockley's partner was driving the police SUV, which chased Smith at more than 80 mph. According to the statement, Stockley is heard on police cruiser camera saying he was "going to kill this [expletive], don't you know it."

VIDEO: Aerials over St. Louis after Jason Stockley decision

After Smith's car slowed down near the intersection of Goodfellow and West Florissant, Stockley told the other officer to ram the car, the probable cause statement said. Then, Stockley approached the car and fired five shots, which all hit Smith. Smith died from the injuries.

Related: Leaders, victim's family call for peace ahead of Stockley decision

The probable cause statement said a gun was recovered from Smith's car but was later found to only have Stockley's DNA on it.

He was charged May 16, 2016, by then-St. Louis Circuit Attorney Jennifer Joyce and taken into custody in Houston, his home at the time.

“We believe we have the evidence we need to prove Mr. Stockley’s guilt beyond a reasonable doubt in a court of law,” Joyce said in a press release at the time.

On Aug. 1 — the first day of the trial — prosecutors laid out their argument, saying Stockley "executed" Smith after the chase, then planted a gun in the slain drug suspect's vehicle as an excuse for opening fire. It was the first time the prosecution publicly revealed their belief that Stockley planted the gun, which only contained Stockley's DNA.

But Stockley's attorney, Neil Bruntrager, said both officers saw the gun inside the car before the chase started. Stockley opened fire only after Smith refused commands to put up his hands and reached along the seat "in the area where the gun was," Bruntrager said.

In testimony on his own behalf on Aug. 8, Stockley said he “had to do what he had to do” and “would violate” any policy if the policy put his life in jeopardy. He also said Smith’s “threat to society was so high, you have to do whatever you can to stop it.”

But the prosecution described a very different scene, with Assistant Circuit Attorney Aaron Levinson saying Stockley shot Smith five times, including once while standing six inches from him, which Levinson called the "kill shot." He said Stockley then returned to the Buick multiple times.

In his testimony, Stockley denied firing any execution-style “kill shot” and defended the trips to the car.

He said one trip was made to retrieve a Quick Clot kit to help stop any potential mass external bleeding. He said he placed it in his pocket and never used it because, upon visual inspection, Smith didn’t have a lot of blood outside his body.

He described his emotional state at the time as “rattled” and “not a good human response.”

“I had just shot someone,” he said.

Stockley also defended entering Smith’s car to retrieve the firearm he believed was in there. “Who better than me to look in the car?” he said.

Related: Local leaders react to Stockley decision

This story continues to develop and will be updated throughout the day.

Court document: Jason Stockley found not guilty of murder

The Associated Press contributed to this story.