Rage by Jonathan Kellerman

Psychologist Alex Delaware and LAPD homicide detective Milo Sturgis revisit an eight-year-old murder of a two-year-old by a couple of teenagers when slow-witted Rand contacts Alex and wants to talk to him. The meeting never takes place as Rand is murdered. As Delaware and Sturgis retrace their steps through a grisly murder case that devastated a community, they discover madness, suicide, and even uglier truths waiting to be unearthed. I think I had read this one before, but wasn't sure until I got to the place that made it all come back. A really good read. Sandy P