In the previous post in this series, I highlighted a wide gap in the incarceration rates of Indiana and Minnesota, with Wisconsin in the middle.  The ordering of the three states from highest incarceration rate to lowest corresponds with the ordering from highest rate of violent crime to lowest.  However, for reasons I explained in the previous post, I don’t think  we ought to end our analysis with the simple assertion that high crime drives high incarceration.  For one thing, there is Minnesota: with a crime rate only a little lower than Wisconsin’s, Minnesota has an incarceration rate that is much lower.  There must be other factors at play besides just the crime rate to account for Minnesota’s incarceration rate.  For another, to focus on the crime-incarceration connection begs the question of what drives the very different crime rates of the three states.

In this post, I’ll explore another possible way of accounting for differences in the three states’ incarceration rates, the racial threat hypothesis.  The basic idea is this: a larger racial minority population causes the majority to feel more threatened by the minority and consequently to prefer to stronger social control measures.

Here are the relevant numbers from Indiana, Wisconsin, and Minnesota:

As you can see, the incarceration-rate order tracks the order based on the size of the each state’s black population.

In the first post in this series, I highlighted a sizable gap between the incarceration rates of Minnesota and Wisconsin.  Although the two states have similar crime rates, Wisconsin has more than twice Minnesota’s incarceration rate (651 per 100,000 versus 310).

In this post, I cover racial disparity data in the two states.  As summarized in a helpful new article by Michael Rocque (“Racial Disparities in the Criminal Justice System and Perceptions of Legitimacy: A Theoretical Linkage,” 1 Race & Justice 292 (2011)), a substantial body of research documents wide racial disparities in the American criminal justice system.  Consistent with the national data, and despite longstanding reputations for progressive politics, both Minnesota and Wisconsin exhibit troublingly large disparities in white and black incarceration rates.