Why is Canistota, South Dakota so murdery, by murders?

The hotspot is one town: Canistota, with three murders, all of them covered in one episode. It is the only town in McCook County involved, in the south-east corner of South Dakota. Canistota covers a little over half a square mile and has 638 people. Sioux Falls is about forty minutes away, close enough to the city to be somewhere on the way to somewhere else.

The town dates from 1883, when the Chicago Northwestern Railroad chose the site and laid it out in seventy-two blocks. It was incorporated in 1900. A railroad man named it after his home town in New York, and a clerical error on the post office application left the town and its post office spelling the name differently until 1919. For much of the last century the local economy rested on a chiropractic clinic, a family dynasty that had been cracking backs since about 1915.

The murders are three killings in the mid-1990s, in August and November 1994 and July 1996, all within the town, all carried by a single episode, episode 72, which aired in 2018.