Former suburban Minneapolis police officer Kim Potter took the stand Friday at her manslaughter trial in the shooting death of Black motorist Daunte Wright.

Potter, 49, has said she meant to draw her Taser instead of her gun when she shot the 20-year-old Wright during an April 11 traffic stop as he was trying to drive away from officers seeking to arrest him on a weapons possession warrant. Video of the shooting recorded by officers’ body cameras recorded Potter shouting "I'll tase you!" and "Taser, Taser, Taser!" before firing once.

Besides arguing that Wright's death was a tragic mistake, Potter's attorneys have also said that she would have been justified in using deadly force to stop Wright from driving away and possibly dragging one of Potter's fellow officers.

Before Potter took the stand, a witness called by her lawyers testified that police officers can mistakenly draw their guns instead of their Tasers under high-stress situations because their ingrained training takes over.

Laurence Miller, a psychologist who teaches at Florida Atlantic University, said Friday that the more someone repeats the same act, the less they have to think about it and there can be circumstances during a stressful situation in which someone’s normal reactions may be "hijacked."

The death of Wright set off angry demonstrations for several days in Brooklyn Center. It happened as another white officer, Derek Chauvin, was standing trial in nearby Minneapolis for the killing of George Floyd.

Prosecutors argue that Potter was an experienced officer who had been thoroughly trained in the use of a Taser, including warnings about the danger of confusing one with a handgun. They have to prove recklessness or culpable negligence in order to win a conviction on the manslaughter charges.

Miller said that when a person learns a new skill, memory of an old skill might override that, resulting in an “action error” in which an intended action has an unintended effect.

"You intend to do one thing, think you’re doing that thing, but do something else and only realize later that the action that you intended was not the one you took," he said.

Miller said it happens all the time and is often trivial, like writing the wrong year on a check early in January. There are also more serious examples of action error, such as when a doctor might use an old approach to treat someone even after being trained in a newer one, he said.