Prosecutors on Thursday rested their case in the first-degree murder trial of Jason Van Dyke, a white Chicago police officer accused of fatally shooting Laquan McDonald, a black teenager, 16 times.

McDonald’s death roiled Chicago, led to impassioned demonstrations and exposed deep resentment and mistrust between officers and the people they're sworn to protect.

Special Prosecutor Joseph McMahon called the 2014 killing “completely unnecessary” and argued that race had been a factor.

Prosecutors say that on the night McDonald was shot and killed, the only thing the defendant saw was a “black boy walking down the street” who had the “audacity to ignore the police.”

OPENING ARGUMENTS BEGIN IN THE MURDER TRIAL OF WHITE CHICAGO COP WHO SHOT BLACK TEEN

Van Dyke is charged with first-degree murder, 16 counts of aggravated battery and one count of official misconduct in McDonald’s death. He was suspended without pay and has pleaded not guilty to murder.

His attorneys have painted McDonald as a troubled teen who refused to drop the three-inch retractable knife he'd been carrying the night he was killed.

Defense attorney Daniel Herbert described McDonald as an “out-of-control individual who didn’t care about anyone,” and argued that Van Dyke was a “scared police officer who was fearful of his life and the life of others.”

Van Dyke claimed he shot McDonald 16 times when the teen swung a knife at him. Grainy dashcam video — released 13 months later after a court order — showed McDonald holding a knife at the side of his body, about 15 feet away from Van Dyke, and walking away from him and other officers who'd responded to a report that the youth was trying to break into vehicles.

McDonald fell to the pavement less than two seconds after he was shot. Van Dyke continued shooting for another 12 seconds, emptying his 16-shot semiautomatic gun.

Eury Patrick, the prosecution’s expert on deadly use of force by the police, testified Thursday that Van Dyke kept shooting “long beyond the point of being reasonable.”

“They’re not trained to just empty their gun,” Patrick said. “It’s not a knee-jerk reaction. They’re trained to shoot until the risk is ended.”

Witness Jose Torres told jurors he heard more gunshots after McDonald fell than before.

“I’m not going to use the word, but I said, ‘Why the "f" are they still shooting him if he’s on the ground?'”

CHICAGO JUDGE SLAPS WHITE COP ON TRIAL FOR LAQUAN MCDONALD MURDER WITH $2G FINE FOR VIOLATING GAG ORDER

Over the course of the week, prosecutors showed the jury --eight women and four men -- the dashcam video more than a half-dozen times. They also showed the jury every gunshot wound on McDonald’s body.

On Wednesday, Cook County Medical Examiner Dr. Ponni Arunkumar spent two hours on the stand, detailing the multiple bullet holes on McDonald’s back, chest, leg, arms and hand. She also pointed out where the bullets had burned McDonald’s skin, shattered his bones and ripped through his lung. She testified they picked bullet fragments from his teeth and mouth.

The Rev. Jesse Jackson showed up at the Chicago courthouse on Wednesday afternoon. He watched an hour of testimony and told reporters that the McDonald case was “one of the most heinous crimes since Emmitt Till.”

Till, who was born in Chicago in 1941, was savagely beaten and killed in a racially motivated attack in Mississippi when he was 14. He was abducted, beaten and shot in the head. His killers, who later confessed to the crime, were acquitted.

Van Dyke’s partner and two other officers face trials this fall on conspiracy and obstruction of justice charges. Prosecutors contend that they lied to protect Van Dyke, filing reports that echoed his statement characterizing McDonald as a danger.