Why is Streamwood, Illinois so murdery?

Streamwood sits in Cook County, a Chicago suburb that was farmland within living memory: about 800 people and mostly farms in 1950, dairy country since the 1830s, incorporated in 1957 alongside Bartlett and Hanover Park as the Tri Village. Then veterans came home from the Second World War and Korea and bought houses with the GI Bill. By 2020 the population was 40,615. That is the classic shape of a town the show keeps finding: the edge of a big city, grown fast, with a lot of new streets and not much history behind them.

Its 29 murders across 9 episodes are not one bad decade. The cases run from 1966 to 2007, with a cluster in the 1970s and 1980s and more in the 1990s and 2000s. Eight of the 29 belong to a single episode set in Streamwood itself, episode 184. The rest are scattered: three victims here, four there, one in another. So the town tops the league on one big case plus a wide ring of smaller ones within 25 miles.

None of this is a crime statistic. It counts the cases the show chose to cover, and the show picks the towns.