Progress already made in 2012 reduces the potential impact of repealing mandatories.

The 2012 reductions — to the school zone, the second offense penalties and the trafficking penalties — reduced the population of drug offenders in the state prison and the Houses of Correction, now at roughly 15% at both levels. Even without further legislative action, the population could drift down further, but that is not certain.

Among drug incarcerations, mandatories of 5+ years account for only 8% of person-years sentenced.

In thinking about the consequences of repealing mandatory minimums, it is important to recognize that the longest sentences, where the greatest injustices can theoretically occur, are rare. The likely outcome change resulting from shifting power from the prosecutor to the sentencing judge by repealing mandatory minimums is therefore more limited than one might infer from the most egregious examples.

Most drug arrests do not result in conviction, much less incarceration.

According to FBI reports, there were 11,599 arrests for drug offenses in Massachusetts in calendar 2012. Using dispositions in Fiscal Year 2013 (starting six months into calendar 2012) as a proxy for the dispositions of these arrests, it appears that only 4,583 of these cases resulted in a conviction. So, approximately 7,000 were disposed of without a conviction being entered — through dismissal, continuance without a finding, or otherwise.

Drug offenses account for a higher fraction of Hispanic incarcerations.

As a share of incarcerated inmates, drug offenders represent a larger share among Hispanics, but the drug offense share has gone down. A study done in the mid-90s of the state prison population had drug commitments accounting for almost half of the Hispanic state prison population. 2015 statistics put the percentage of drug commitments by Hispanic prisoners at closer to 25 percent.

Incarceration rates vary by race/ethnicity.

The Prison Policy Initiative has compiled incarceration rates by race/ethnicity using data from the 2010 census. While Massachusetts’ white and black incarceration rates are low among states, its black rate is 6 times its white rate. Massachusetts’ 1:4 white-Hispanic incarceration rate disparity is roughly equal to its white-Hispanic poverty rate disparity.