Why is the Delmar, New York area so murdery, by murders?

Delmar is a hamlet inside the town of Bethlehem, fifteen minutes outside Albany and home to about 17,100 people. In 2004 it was a quiet suburban place. The detective bureau had four detectives and no homicide squad, because there'd been only about three murders in forty years. One night that November supplied two of the five murders in this hotspot (episode 733).

The other three belong to Stillwater, a village in Saratoga County 24 miles north, and they came as three separate cases: February 2000, March 2010, and some months after July 2012. Three killings across a decade and more, in a place tied to the first by upstate New York and a distance that still counts as local (episode 149).

That leaves the Delmar area 81st overall and second in New York: a double killing in a commuter hamlet, plus a long, patient accumulation in a village up the road. Two towns and five deaths, and a hotel put up in 1836 that served as Bethlehem's town hall from 1950 to 1980.