AP Photo/City of Ferguson, File
The grand jury has decided not to indict Ferguson Officer Darren Wilson.
Wilson, who is white, shot Michael Brown after stopping him and a friend for walking in the street.
Wilson has said he shot Brown in self-defense. He reportedly told investigators that there was an altercation in his police vehicle before he shot the teenager. Wilson said Brown was reaching for Wilson's gun.
Brown's autopsy report seemed to support Wilson's version of events, according to experts who spoke to the St. Louis Post-Dispatch last month. Brown's wounds seem to suggest that he was facing Wilson when the deadly shot was fired.
But other witnesses have told a different story. Some claim Brown had his hands up in a sign of surrender and was running away when he was shot.
Protests, which at times turned violent, erupted in the St. Louis suburb of Ferguson, Missouri in August after Wilson shot Brown.
Police and federal authorities have been preparing for more protests in light of the grand jury decision.
There seems to be little chance that Wilson will face federal civil rights charges for the shooting. Sources told The Washington Post last month that the Justice Department didn't have a strong enough case to charge Wilson and prove beyond a reasonable doubt that he intended to violate Brown's constitutional rights.
The Justice Department has also been investigating the policing practices of the Ferguson Police Department. Attorney General Eric Holder has said "the need for wholesale change in that department is appropriate."