Darius Simmons Murder: John Henry Spooner, Wis. man, 76, guilty in fatal shooting of 13-year-old teen neighbor

(CBS/AP) MILWAUKEE- John Henry Spooner, a 76-year-old Milwaukee man, was found guilty Wednesday of fatally shooting his 13-year-old neighbor whom he suspected had broken into his home and stolen weapons. The trial now shifts into a second phase in which the defense will try to prove the defendant was mentally ill at the time of the shooting.

A jury convicted Spooner of first-degree intentional homicide in the May 2012 killing of Darius Simmons. Surveillance video taken from Spooner's own security cameras showed him confronting the teen that morning, pointing a gun at him from about 6 feet away and shooting him in the chest.

Spooner had entered two pleas to the homicide charge: not guilty and not guilty by reason of mental disease or defect. That set up the trial to be conducted in two phases: one to determine whether he was guilty of the homicide, and if so, a second to determine his mental competence at the time.

Spooner's defense attorney, Franklyn Gimbel, has said he has an expert who will testify that Spooner was suffering from mental disease at the time of the shooting that prevented him from knowing right from wrong.

Gimbel conceded from the outset that his client shot Darius. However, he argued that Spooner did not intend for the gunshot to be fatal.

The surveillance video provides a clear view of what happened. Spooner emerges from his house and confronts the teen, who is retrieving his family's garbage cart from the street. Spooner points a gun at Darius, who quickly moves back a few steps. Spooner

then talks to Darius' mother, who's standing on her porch out of view of the camera, and Spooner briefly points the gun in her direction. Moments later, Spooner points the gun back at the boy standing a couple of feet in front of him. He fires, hitting Darius in the chest.

The teen stumbles and runs away, and Spooner fires a second shot that misses.

The mother, Patricia Larry, testified that she chased Darius to where he collapsed in the street and held him in her arms as he died.

"I pulled his shirt up and I (saw) he had a bullet hole in his chest," she testified tearfully. "He took one more breath and that's it."

Spooner paced up and down the sidewalk until police arrived a few minutes later. Police officer Richard Martinez testified that he was handcuffing Spooner when Spooner acknowledged, "Yeah, I shot him."