Why is Sanford, Maine so murdery?

Sanford sits in the little panhandle of southern Maine that presses against New Hampshire, not too far from Old Orchard Beach. The Mousam River runs through it and once powered its industry: a saw mill there as early as 1745, then the Goodall mills from 1867, turning out mohair plush for railway seats and Palm Beach fabric for summer suits. When the nation's largest textile firm bought the mills in 1954 and closed the plants, the town's economy was ruined for a while. It is a mill town of about 21,000 that has diversified since, biotech included.

Its 13 murders arrive in six episodes spread across six towns, and only one happens in Sanford itself. The rest ring the town at eight, 18, 21, 23 and 24 miles, down towards the coast. No single case carries the count: one episode has four victims, two have three, and three have one apiece.

The cases fall across the decades, from 1984 to 2012, so this is not one bad year but a radius the show keeps returning to. It counts the show's cases, not the town's crime statistics; the show picks the towns.