The supervisor of a white Oklahoma police officer who shot an unarmed black man testified Thursday that he told her to say nothing about the incident because he knew the shooting would be racially explosive.

Tulsa police Cpl. Wyett Poth testified Thursday about his directions to Officer Betty Jo Shelby after the shooting of Terence Crutcher. He said he walked up to Shelby at the shooting scene to make sure she knew she had the right to say nothing.

"I told her not to say a word. I knew there was going to be a group of people that didn't like what happened simply because of the color of somebody's skin," he testified.

The testimony came in the second day of Shelby's manslaughter trial for the Sept. 16 shooting.

Crutcher's SUV had stalled in the middle of a city street. Shelby, 43, had said the 40-year-old Crutcher wasn't obeying commands and kept reaching for his pockets, and that she shot him because she thought he was reaching into his vehicle for a gun. Crutcher didn't have a gun on him or in his SUV.

Prosecutors argued during their opening statement that Shelby overreacted when she shot Crutcher last September.

The shooting was captured on police helicopter and dashcam video, and one of the witnesses who testified Wednesday was officer Michael Richert, who was in the helicopter above the scene. In radio chatter moments before Shelby shot Crutcher, Richert said Crutcher looked "like a bad dude" who "could be on something."

Richert's statements outraged Crutcher's family, who said it indicated a racial bias.

On Wednesday, Richert was among the six witnesses who testified that they weren't aware of anything Crutcher may have said or did to signal that he was a threat to the officers on the ground. He told prosecutors he "had no idea" if Crutcher was on something as he watched from above and that his comments weren't based on Crutcher's appearance.

"I was basing those statements on everything in the totality of the circumstances," Richert said.

Richert also testified that he watched Crutcher walk away from Shelby with his hands up. He said it was highly unusual for a person to do that while not complying with commands and while an officer has a gun pointed at him, the Tulsa World reported.

Shelby's attorneys have said Crutcher refused Shelby's commands to lie down during a two-minute period before police cameras recorded the shooting.

Shelby also told police investigators that she believed Crutcher to be high on PCP, a powerful hallucinogenic that can make users combative and unpredictable. An autopsy found the drug in his system, and police said they recovered a vial of it in Crutcher's SUV.