Just before a wave of violence turned Baltimore into the nation’s deadliest big city, a curious thing happened to its police force: officers suddenly seemed to stop noticing crime.
Police officers reported seeing fewer drug dealers on street corners. They encountered fewer people who had open arrest warrants.
Police questioned fewer people on the street. They stopped fewer cars.
In the space of just a few days in spring 2015 – as Baltimore faced a wave of rioting after Freddie Gray, a black man, died from injuries he suffered in the back of a police van – officers in nearly every part of the city appeared to turn a blind eye to everyday violations. They still answered calls for help. But the number of potential violations they reported seeing themselves dropped by nearly half. It has largely stayed that way ever since.