Sacred sins - Nora Roberts

In the lazy days of summer, a merciless heat wave is the biggest story in Washington, D.C. But the weather is knocked off the front pages when a young woman is found strangled to death. A note left behind reads Her sins are forgiven her.
Two more victims soon follow, and suddenly every headline is devoted to the killer the press has dubbed “the Priest.” When the police ask top-notch psychiatrist Dr. Tess Court to help with their investigation, she comes up with a disturbing portrait of a twisted soul.