Controversial Criminal Prediction System Has Colorado Roots

May 23, 2016

Will a criminal re-offend?

A host of data-driven systems have tried to answer that question over the last few decades, to varying degrees of success. Defendants are assigned a "risk score," an easy-to-understand figure that is given to judges during sentencing in many states -- including Colorado.

But ProPublica, a Pulitzer Prize-winning news non-profit, examined more than 7,000 risk scores in Florida and found troubling racial disparities. 

  • The formula was particularly likely to falsely flag black defendants as future criminals, wrongly labeling them this way at almost twice the rate as white defendants.
  • White defendants were mislabeled as low risk more often than black defendants.

ProPublica analyzed scores from an algorithm developed by Northpointe, a company started in 1989 by a Michigan corrections official and Tim Brennan, then a CU statistics professor. 

Brennan told ProPublica that it's important to consider factors that can be correlated with race -- like poverty and unemployment.

“If those are omitted from your risk assessment, accuracy goes down,” he said. He and his co-founder sold the company in 2011.

Northpointe disputes ProPublica's analysis. Read the full piece at ProPublica.org.