A Missouri judge on Friday found a former St. Louis police officer not guilty of murder in the shooting death of a black man after a car chase in 2011, prosecutors said.
Officials feared the verdict could set off violent protests, as have similar deadly cases involving police and minorities have in recent years.
Jason Stockley, 36, who is white, had been charged with first-degree murder, accused of intentionally killing Anthony Lamar Smith and planting a gun in his car. Stockley, who was arrested in May 2016, testified he acted in self-defense.
Judge Timothy Wilson's highly anticipated ruling was announced Friday, more than five weeks after the bench trial ended.
Killings of unarmed black people by U.S. police in recent years triggered widespread protests and activists promised disruptive demonstrations if Stockley was acquitted.
St. Louis and state officials braced for a repeat of the violent protests and racial tensions that followed the 2014 fatal shooting by police of unarmed black teenager Michael Brown in Ferguson, near St. Louis.
Missouri Governor Eric Greitens on Thursday put the National Guard on standby. Some schools called off classes and some events were postponed, according to local media.
Christina Wilson, Smith's fiancée, pleaded at a news conference on Thursday evening for protesters to avoid violence if they demonstrate.
The verdict in St. Louis follows high-profile mistrials or acquittals of police officers charged in shootings in Ohio and Minnesota this year.
(Reporting by Suzannah Gonzales and Chris Kenning; Editing by Bill Trott)