When police spotted Freddie Gray and he took off running through his Baltimore neighborhood, officers decided to give chase, setting in motion his death in custody and rioting in the streets.

Fleeing from police is not, by itself, illegal in America, and the U.S. Supreme Court requires police to have some justification for stopping or questioning someone in a public place.

But courts have set a different standard for high-crime areas, ruling that police can chase, stop and frisk people in such locations. Legal experts say that because he was in a drug-infested area, Gray's decision to bolt on April 12 may have justified the decision by police to pursue and detain him.

Gray suffered a fatal spinal injury in custody. Six officers involved were suspended with pay amid a criminal investigation.