Dead and Blonde by Jean Marcy

PI Meg Darcy and police detective Sarah Lindstrom are thrown together again. This time the case is much too personal -- Lindstrom comes home to find her ex-lover bludgeoned to death in her bed. When it becomes apparent that Lindstrom was the intended victim, Darcy rushes in to try to protect her. But Lindstrom doesn't think she needs protecting, especially by a woman who can't keep her hands to herself when she is around the strikingly handsome six-foot tall Norwegian cop.