Bad blood / John Sandford.

Enhanced descriptions from Syndetics:

Over the course of three novels, Virgil Flowers has become one of the most beloved new characters in crime fiction. "An investigator who can be as analytical as Nero Wolfe and as tough as everybody's favorite Boston badass, Spenser" (Booklist). And in this harrowing thriller, Virgil's got a real problem on his hands.

One late fall Sunday in southern Minnesota, a farmer brings a load of soybeans to a local grain elevator. A young man hits him on the head with a steel bar, drops him into the grain bin, waits until he's sure he's dead, and then calls the sheriff to report the 'accident."

The sheriff quickly breaks the kid down, but the next day he's found hanging in his cell. Remorse? The sheriff's not so sure, and is beginning to wonder if one of her own men is responsible. She has no choice but to bring in outside help in the form of Minnesota Bureau of Criminal Apprehension's Virgil Flowers.

At first glance, the case seems fairly simply, but it quickly gets complicated as Virgil begins to uncover a multi-generation, multifamily conspiracy - a series of crimes so monstrous that even the seasoned detective is dumbfounded. Virgil Flowers has seen plenty in his life, but even he has trouble making sense of this one - and in figuring out what to do next.