Computers are getting pretty good at predicting the future. In many cases they do it better than people. That’s why Amazon uses them to figure out what you’re likely to buy, how Netflix knows what you might want to watch, the way meteorologists come up with accurate 10-day forecasts.
Now a team of scientists has demonstrated that a computer can outperform human judges in predicting who will commit a violent crime. In a paper published last month, they described how they built a system that started with people already arrested for domestic violence, then figured out which of them would be most likely to commit the same crime again.
The technology could potentially spare victims from being injured, or even killed. It could also keep the least dangerous offenders from going to jail unnecessarily. And yet, there’s something unnerving about using machines to decide what should happen to people. If targeted advertising misfires, nobody’s liberty is at stake.
For two decades, police departments have used computers to identify times and places where crimes are more likely to occur, guiding the deployment of officers and detectives. Now they’re going another step: using vast data sets to identify individuals who are criminally inclined. They’re doing this with varying levels of transparency and scientific testing. A system called Beware, for example, is capable of rating citizens of Fresno, California, as posing a high, medium or low level of threat. Press accounts say the system amasses data not only on past crimes but on web searches, property records and social networking posts.
Critics are warning that the new technology had been rushed into use without enough public discussion. One question is precisely how the software works — it’s the manufacturer’s trade secret. Another is whether there’s scientific evidence that such technology works as advertised.