Jury selection is set to being Monday in the trial of an Alabama police officer facing a murder charge in the shooting of a man who had called police and told them he was suicidal.

Officer William Darby is charged with shooting Jeffrey Parker outside his home on April 3, 2018, after Parker called police. Darby was the third officer on the scene and fired while Parker held a gun to his own head, authorities have said.

A Huntsville Police Department shooting review board found Darby had acted within department policy, but a Madison County grand jury indicted him.

The defense contends the killing was justified since Parker refused to drop his gun.

WAAY-TV reports that the district attorney’s office has said they will pull from a jury pool of 60 people.