officers cleared in michael cho shooting

An update on the Michael Cho case... The Orange County District Attorney says the two officers who shot and killed Michael acted legally, because the victim apparently threatened one of them with a tire iron: 2 La Habra police officers cleared in deadly New Year's Eve shooting. According to the D.A., the shooting was "a justifiable homicide":

Michael Cho, 25, was agitated and reacted in a bizarre manner when the officers, with guns drawn, ordered him to drop the weapon, Senior Assistant Dist. Atty. Jim Tanizaki said. Tanizaki, who helped supervise the investigation, said police had responded to calls that Cho was vandalizing cars.

Instead of complying with the officers' orders, he walked away, Tanizaki said. When an officer got in front of him, he said, Cho raised the tire iron as if to hit him.

Both officers fired because they thought Cho, an artist and UCLA graduate, "could and would hurt people," Tanizaki said.

Thanks. This entire case still makes absolutely no sense to me. The article indicates that Michael had been struggling with mental illness, and had a history of violent/suicidal behavior. But there's absolutely no way the officers could have known this. I don't understand how a simple vandalism call could result in a guy being shot eleven times, or why a guy wielding a tire iron requires the use of such deadly, excessive force. This isn't the end of this...