Improbable Cause by J.A. Jance, (J.P. Beaumont Series, Book 5) from by Books In Motion.com

Homicide detective J.P. Beaumont met the blonde on the beach. She was screaming. A dead man lay at her feet. It didn't take Beaumont long to find out the man was murdered. Both the lady and the corpse were members of the State Parole Board. The killer could be seeking personal justice for one of the Parole Board's fatal mistakes. The case was turning into a deadly mixture of politics and passion, a nightmare - one where an experienced cop might not be able to stop a killer motivated by blind vengeance...or obsession.