No Bones About It

Description for NO BONES ABOUT IT by Donna Huston Murray:

IS MAN'S BEST FRIEND ALSO HIS DEADLIEST ENEMY?

The dog days of Bryn Derwyn Academy's summer holidays yawn ahead for Ginger Barnes--headmaster's wife, mother of two teenagers and occasional detective. But the tedium is soon shattered when Dr. Karl Vogel, an elite Philadelphia diet guru, is found chewed to death right beside his bloody-mouthed German shepherd, Tibor. And his ex-wife Linda--a dog trainer with whom he shared custody of this prized pet--is arrested for programming Tibor to be a lethal weapon.

Linda, denying everything, beseeches her old schoolmate Gin to save Tibor from being put down. But who else would murder the good doctor? To hound down the killer, Gin must investigate snarling patients, animal activists, a secretary fired for getting fat, canine teeth prints, and the devious, deadly patterns of the human mind.

This is #4 in A Ginger Barnes Main Line Mystery.