Why is the Brighton, New York area so murdery, by episodes?

Brighton is Rochester suburbia with an English name. It was named for Brighton in England. English colonists were putting up permanent structures there around 1790, and the town was formally established in 1814, which makes it one of the oldest in Monroe County. About 37,000 people live there now. Seven miles away sits Penfield, another Monroe County town of roughly 39,000, fifteen minutes outside Rochester.

Its three deaths are politely spaced: February 1982, July 1991, July 2003. Episode 557 carries two of them, nine years apart, following a couple who married in 1974, moved to Colorado for a master's degree and had a daughter in 1978. Episode 457 adds the third, in Penfield: a twenty-six-year-old mother of two small sons, killed as she slept on a pull-out couch in the family living room, with the plot put together over the previous year out of affairs, cocaine and a custody fight.

The three deaths sit in two episodes, in two neighbouring towns.