1 Book Found

Based on your description:

"a series police procedural about a girl found dead near her home. Her family is fanatically religious. It turns out that her father killed her accidentally. The book is from the 80's. The main character is a male police officer investigating the death of a teenage girl from a fanatical religious family. The girl is going to a friend's to change out of her "proper" clothes and into slinky revealing outfits. She ends up dissappearing to having an abortion. In the end it turns out that her father has killed her accidentally. The police officer figures it out because one of his children has done something stupid and dangerous and his reaction to seeing"