A Baltimore, Maryland jury has begun deliberating the case of a police officer charged in the death of Freddie Gray - the young African American man who was fatally injured in the back of a police van in April.
Officer William Porter, who also is black, is the first of six Baltimore officers to be tried in Gray's death.
Porter faces charges of involuntary manslaughter, second-degree assault, reckless endangerment and misconduct. He has pleaded not guilty.
Prosecutors allege that Porter and the other officers failed to help Gray, who suffered a severe spinal cord injury in the van. Authorities have called the vehicle a "casket on wheels."
Gray was handcuffed and shackled by his feet, but not buckled in the seat, allegedly causing his body to slam against the side of the van, severing his spinal cord and leaving him in a coma.
Prosecutors say Porter ignored Gray's pleas for medical help.
"With great power comes great responsibility," prosecutor Janice Bledsoe told the jury in her closing arguments. "Porter had the opportunity on four or five occasions to wield his power to save Freddie Gray. He abused his power. He failed his responsibility."
Defense attorney Joseph Murtha called Gray's death a horrible tragedy, but argued there is no evidence to convict. He said Gray denied needing urgent medical help when Porter asked him.
"The absence of real evidence raises much more than reasonable doubt. This case is based on rush to judgment and fear. What's an acronym for fear? False Evidence Appears Real."
Baltimore Mayor Stephanie Rawlings-Blake is urging city residents to stay calm and accept the verdict.
Violence broke out on the day of Gray's funeral in April, including arson, looting and rocks and bottles thrown at police. But Baltimore's black leaders say the riots were not just about Gray but also about what they say has been a city government that has long ignored the needs of poor African American neighborhoods.
Gray, who had been in trouble with the law in the past, was arrested in April for reasons that are still not entirely clear.