Blake Neff of the Daily Caller explains the flaws in a new study purporting to show that the American justice system is racist.
A major article widely cited as proof of racial bias in the criminal justice system is actually anything but.
According to ProPublica’s May article “Machine Bias,” a popular risk assessment software program, used across the country to evaluate criminal defendants’ risk of reoffending, has extremely biased outcomes against black defendants compared to white ones.
The article’s findings have started to take off. Immediately after publication, it was cited on sites like The Daily Dot and Fusion. On June 25, The New York Times cited it as proof that both computer algorithms and law enforcement are substantially biased against blacks. Last week, it was touted by FiveThirtyEight’s science reporter.
But ProPublica’s conclusions are deeply flawed, representing a major error in statistical reasoning on the part of its staff. …
… ProPublica was commendably open about its research methods, as they not only wrote a separate article just on their methodology, but also posted all of their data and computer code on GitHub. The transparency makes it easy to follow how ProPublica analyzed the data and reached its conclusions.
In its methodology, ProPublica does check for the kind of bias described above. And the results are encouraging: There’s no evidence it exists.
