Why is Caledon, Ontario so murdery, by episodes?

Caledon is in Peel Region, southern Ontario, about an hour outside Toronto, and grew from a township of small villages into a place of roughly 70,000. In 1869 one of those villages, Belfountain, had a population of 100, stage coaches running through it and land lots selling for $20. A century later, in 1973, Caledon took in more territory when another town dissolved, and most of the sections north of Mayfield Road came its way. It is commuter country, with a lot of quiet road in it.

All seven of its murders come in a single episode, episode 381, and all of them fall in one tight stretch of the early 1990s. The first is October 1991, and the rest follow in April 1992 and across June and July of that year. A forty-seven-year-old woman vanished from a gift shop in Toronto where she worked, and her blood-stained car turned up in a ditch near Caledon a couple of days later. Months on, a skeleton, probably hers, was found in the woods 457 metres from where the car had been left.

Seven victims in one episode puts Caledon at 139 overall, and top among the Ontario hotspots.