The Missouri grand jury chose not to indict Darren Wilson, the white police officer who shot and killed black teenager 18-year-old Michael Brown on a street in Ferguson, Missouri in August.
The prosecuting attorney says no probable cause existed to file any charges.
According to NBC News, the family of Michael Brown was notified that Wilson will not be indicted for the shooting.
A grand jury considered the evidence for three months. It had the option of returning a charge as severe as first-degree murder against 28-year-old Wilson. It also had the option of a lesser charge, or no charge at all.
Robert McCulloch, the St. Louis County prosecutor, announced the decision during a news conference. He said that some statements from witnesses to the Aug. 9 shooting were “completely refuted by the physical evidence.”
“Eyewitness accounts must always be challenged and compared against the physical evidence,” he said.
In a statement, the Brown family said: “We are profoundly disappointed that the killer of our child will not face the consequence of his actions.”
Gov. Jay Nixon readied the National Guard and pledged that law enforcement would focus on protecting lives, property and free speech.
“Our shared hope and expectation is that, regardless of the decision, people on all sides show tolerance, mutual respect and restraint,” he said.
Charlie Dooley, the St. Louis County executive, was more blunt: “I do not want people in this community to think they have to barricade doors and take up arms,” he said. “This is not a time to turn on each other. This is a time to turn to each other.”
The grand jury was composed of six white men, three white women, two black women and one black man, selected at random from St. Louis County, which is about 70 percent white. Ferguson, a city of 21,000 people, is about two-thirds black. It takes nine of 12 votes to indict.
The Justice Department is conducting a separate investigation into possible civil rights violations that could result in federal charges. The department also has launched a broad probe into the Ferguson Police Department, looking for patterns of discrimination.
NBC News and the AP contributed to this report.