Recent focus on corrections reform has drawn attention to the state’s relatively low incarceration rate. In national data, Massachusetts’s incarceration rate appears slightly low because more offenders are held in county jails and fewer are held in state prison facilities. Adjusting for this policy is difficult. The federal government has not released  state jail population estimates since 2006 . 

The Prison Policy Initiative provides estimates that account for this problem by collecting decennial Census redistricting data that capture offenders held in state, county, and federal correctional institutions. The inclusion of federal inmates distorts these estimates slightly, but they are still the most comparable state incarceration rates available. They show Massachusetts had 377 inmates in prisons in jails per 100,000 residents in 2010. Only five states had lower incarceration rates: North Dakota, New Hampshire, Rhode Island, Maine, and Vermont.

But many have pointed out that comparing Massachusetts to the US outlier is not the best measure of whether the Commonwealth—which has tripled the percentage of the population in prisons and jails since the1980s—is using incarceration most effectively.

The Prison Policy Initiative’s data show that in comparison to other countries, Massachusetts has come to rely heavily on incarceration. Massachusetts’s incarceration rate is 2.5 times higher than Spain, 3 times higher than China and Canada, and nearly 5 times higher than Germany.

Data from the Prison Policy Initiative also suggest that incarceration rates for racial and ethnic minorities in Massachusetts look much more similar to the nation’s troubling figures. The incarceration rate for white residents in Massachusetts is about half the national rate for whites, but the incarceration rate for black residents in Massachusetts is about two-thirds of the alarmingly high US rate, and for Hispanics it actually exceeds the national incarceration rate by 12 percent.