Rise of the racist robots – how AI is learning all our worst impulses

In May last year, a stunning report claimed that a computer program used by a US court for risk assessment was biased against black prisoners. The program, Correctional Offender Management Profiling for Alternative Sanctions (Compas), was much more prone to mistakenly label black defendants as likely to reoffend – wrongly flagging them at almost twice the rate as white people (45% to 24%), according to the investigative journalism organisation ProPublica. Compas and programs similar to it were in use in hundreds of courts across the US, potentially informing the decisions of judges and other officials. The message seemed clear: the US justice system, reviled for its racial bias, had turned to technology for help, only to find that the algorithms had a racial bias too. How could this have happened?