Sentencing more biased by race than by class

Yesterday  I was super happy to be passed along this amazing blogpost from lawyerist.com called Uncovering Big Bias with Big Data and written by David Colarusso, a lawyer who became a data scientist (hat tip Emery Snyder).

For the article, David mines a recently opened criminal justice data set from Virginia, and asked the question, what affects the length of sentence more: income or race? His explanation of each step is readable by non-technical people, it’s a real treasure.

And, unsurprisingly to those of us who have thought about this, the answer he came up with is race, by a long margin, although he also found that class matters too.

In particular he fit his data with the outcome variable set to length of sentence in days – or rather, log(1 + that term), which he explains nicely – and he chose the attributes to be the gender of…