Predicting crime before it happens
Christopher Beam for Slate explains research being done at UCLA in collaboration with the LAPD on predictive policing:
Predictive policing is based on the idea that some crime is random—but a lot isn't. For example, home burglaries are relatively predictable. When a house gets robbed, the likelihood of that house or houses near it getting robbed again spikes in the following days. Most people expect the exact opposite, figuring that if lightning strike once, it won't strike again. "This type of lightning does strike more than once," says Brantingham. Other crimes, like murder or rape, are harder to predict. They're more rare, for one thing, and the crime scene isn't always stationary, like a house. But they do tend to follow the same general pattern. If one gang member shoots another, for example, the likelihood of reprisal goes up.
This happened in my neighborhood when I was in fifth grade. We lived in a pretty quiet neighborhood, but one morning a window was open. Someone had come into our house while we were sleeping and stole whatever was in immediate reach. They also stole my dad's brand new bicycle from the garage. Same thing happened to my neighbor two days later.