The Bitterroots by C.J. Box

Cassie is a tough P.I. who used to be a tough cop in Montana. She has been hired to do some fact checking on a case involving a man from a cowboy mafia family who supposedly raped his young niece. As much as she wants to lock up this guy some of the "facts" just aren't sitting well. The more she looks into things the tighter the noose that this influential family has around her neck becomes. It is hard to look for justice in a town that seems to be bought and paid for by this awful family. Solid police/ western thriller with a great big-hearted female character that you want to hear more from.