Watch any TV police drama and chances are, the episode follows the same script. After several riveting twists and turns, the clever detectives, using the latest computers, equipment, and intelligence, track down the bad guy. Crimes are committed, crimes are solved, arrests are made.
In police parlance, this is called the “clearance rate,” or the rate at which a given type of crime ends in an arrest within a year. And we’re bad at it.