Why is Jackson, New Hampshire so murdery, by murders?

Jackson is a town of 998 people in Carroll County, in the White Mountains at the far eastern edge of New Hampshire, close to the Maine border. It started as New Madberry, named after the place in the UK, and by 1800 it was Adams, after a president. A road went through Pinkham Notch in 1772 and settlers arrived in 1778. The population has stayed modest ever since.

All three murders in the hotspot come from one episode, episode 498, in January 1985. One episode, three victims, one winter in the mid-1980s. Jackson ranks 175 overall and third in New Hampshire.

The episode concerns a family who ran an inn in the notch country: two parents and two children. The whole hotspot's count is three victims, all from that one January. A lot of weight for one month to carry, and a record that looks like a single bad winter in a small mountain town.