Sometimes you want to know why? in the worst way.

The final police report on the Trolley Square shootings a year ago will tell you in detail how Sulejman Talovic walked through the mall with a shotgun and a handgun, killing five people and wounding four before police killed him.

Why? No one knows.

If you've been on this planet for more than a few years, you know the human heart can be a dark place.

Eighteen-year-old Talovic saw his share of darkness. He told a friend how he had hidden as a child in a Bosnian wood, face down in the dirt as Serbs decapitated Muslims. He watched people executed with a shot to the head.

He also anticipated the Trolley Square massacre would be the "happiest day" of his life.

Read all you can on the tragedy. Try to figure it out. You can get more stories at the Trib. The DNews also has the full report and schematics.

You can't do any worse in explaining it than the criminologists. A University of South Florida expert in kids who murder, for example, offers this: "In a lot of these cases, you do see . . . that this is a troubled individual. Happy, healthy individuals don't go out and do this."