A judge acquitted a Baltimore police officer of manslaughter and other charges Monday in the death of Freddie Gray, a black man who was critically injured in a police transport van.

A Baltimore judge is poised to deliver his verdict in the murder trial of an officer who drove the police van where a black arrestee's neck was broken, triggering some of the worst riots the city has ever seen.

Prosecutors introduced a new theory as a murder trial started for a police van driver charged in the death of Freddie Gray, a black man whose neck was broken in the back of the wagon.