Why is the Farmington, New Mexico area so murdery, by episodes?

Farmington is in the northwest corner of New Mexico, in San Juan County, close to the Four Corners. Three rivers meet nearby, which is how it started as Junction City; by 1901 it was Farmington, incorporated, with 548 people. It now has about 46,700, and the show introduces it as a town with high crime and a difficult reputation. In 1950 more than half the town reported saucers overhead. In 1967 a nuclear device was detonated fifty miles east to crack the bedrock and free more gas. Dull it is not.

The Farmington area's five murders come from two episodes and two towns. Farmington supplies four, across three cases from November 1996 to June 2000, all in one episode. Flora Vista, six miles out, supplies the fifth: a seventeen-year-old killed in February 1994, in a small house on the outskirts. One episode carrying four of the five does most of the work, and the second episode adds one more.

Six miles is not much of a gap. On this map Flora Vista is Farmington's near neighbour, and the two make one patch of San Juan County.