ST. PAUL, Minn. (AP) — An expert on police use of force says a Minnesota officer who fatally shot a black motorist during a traffic stop last July had no reason to believe that the man was a threat.

Jeffrey Noble testified Wednesday in the trial of Jeronimo Yanez.

The St. Anthony police officer is charged with manslaughter in the death of Philando Castile. Yanez shot Castile after the motorist told him he was carrying a gun. Castile's girlfriend livestreamed the aftermath on Facebook.

Noble says Yanez's actions were unreasonable. Under questioning from prosecutors, he went through squad car video, saying Yanez should have acted differently in several instances. For example, he said Yanez should have ordered Castile to put his hands on his steering wheel or dashboard.