Remember Minority Report? Yeah, that sci-fi flick starring Tom Cruise (before he jumped on Oprah's couch) and Colin Farrell (back when people thought he was a real movie star). In the film, "precogs" sleep in a creepy pool in some basement laboratory and predict which citizens will commit murder. They communicate their predictions through a machine that spits out a mini billiards ball with the culprit's name on it. The police use those predictions to arrest citizens before the murder can take place and the "killers" are sent to jail because, science.
All caught up? Good.
Well, Philly and Baltimore (and, soon, D.C. and the rest of the country) are kind of sort of doing something similar.
Note: They're using it in Baltimore, which means this is the part when you're supposed to imagine what it would have been like if Kima and company were using this software.