How many inmates are incarcerated by the Massachusetts Department of Correction (DOC)?
On January 1, 2015 there were 9,670 criminally sentenced inmates in the jurisdiction of the DOC. There were 537 offenders incarcerated as a civil commitment and 606 pre-trial detainees in the DOC. The total jurisdiction population was 10,813.

How many Massachusetts inmates are incarcerated in other jurisdictions' facilities?
On January 1, 2015 there were 87 DOC inmates housed in other state or federal correctional facilities; 279 DOC inmates were housed in county correctional facilities.

How many institutions do you have and how many security levels are there?
The Department has 18 institutions and 4 security levels: Maximum, Medium, Minimum and Pre-Release.

What is the DOC overcrowding rate? 
The total custody overcrowding rate for DOC facilities as of December 29, 2014 was 130%. The overcrowding rate for medium security facilities was 139%. Overcrowding rate is based on a snapshot at the end of 2014.

What is the average cost to house an inmate per year? 
For Fiscal Year 2014, the average cost per year to house an inmate in the Massachusetts DOC was $53,040.87.

How many people are committed to the DOC in a year?
There were 2,730 new criminal court commitments to the DOC during 2014; 1,972 males and 758 females.

How many people are released from the DOC in a year?
During the year 2014, there were 3,299 criminally sentenced inmates released from both DOC facilities, as well as facilities in other jurisdictions. Of these releases, 2,535 (77%) were released to the street: 693 via parole, 1,770 through expiration of sentence and 72 court release/drug lab. Of the 3,299 inmates released, 887 were female and 2,412 were male.

What is the average time served?
The estimated time served for state criminally sentenced males, including all inmates released to the street from a sentence at the DOC due to expiration of sentence, parole, court release, or payment of fines in 2013, was about 3.6 years.  For females, the average time served for state criminally sentenced releases to the street was about 2.8 years; and 115 days (about 3.8 months) for county criminally sentenced releases to the street.  Inmates with life sentences were not included in the above noted numbers due to significantly longer stays and differences in sentence structure.


Time served is calculated by adding together an inmate’s jail credits and their length of stay[1]. To clarify, each is defined as:

Jail credits are days of credit for time served awaiting trial. The DOC does not award or take away jail credits; pre-trial confinement is determined by the courts.

Length of stay is the total number of days an inmate is incarcerated on the same DOC commitment number within the DOC jurisdiction population; the total number of days may include time from multiple admission and releases on that same commitment number.

Time Served is defined as the sum of an inmate’s total length of stay on the same commitment number within the DOC jurisdiction population including jail credit days.


What is the recidivism rate?

A 3 year recidivism study of 2,725 criminally sentenced inmates released from DOC institutions in 2010[2] yielded the following results: within the first year post-release 581 (21%) of the 2,725 released inmates recidivated, an additional 311(11%) recidivated in the second year post-release, and another 185 (7%) recidivated within the third year post-release. The overall recidivism rate for inmates released in 2010 over the span of 3 years was 39%.  

The Massachusetts Department of Correction (MADOC) defines a recidivist as any criminally sentenced inmate released to the street from MADOC jurisdiction who is re-incarcerated in a Massachusetts state or county facility or to a federal facility for a criminal sentence within three years of their release to the street.

 How many "lifers" are incarcerated in Massachusetts DOC facilities?
On January 1, 2015, there were 2,018 inmates serving a life sentence. Of the 2,018, there were 1,009 inmates serving a first-degree life sentence while the remaining 1,009 were serving a sentence of second-degree life (982) or an out of state life sentence (27).

What is the gender breakdown of the inmate population?
Of the 9,670 criminally sentenced inmates in DOC jurisdiction on January 1, 2015, 514 (5%) were female and 9,156 (95%) were male.

What is the racial/Hispanic ethnicity composition of the inmate population? Inmates serving criminal sentences on January 1, 2015 reported the following race/ethnicity: White 4,152 (42.9%), Black 2,732 (28.3%), Hispanic 2,516 (26.0%), Asian 132 (1.4%), American Indian/Alaskan Native 50 (0.5%), and Other 88 (0.9%).



Date last updated: March 2015

[1] All measures of inmate time served, or percent of time served, were done using Huber’s M-Estimator, a robust, non-parametric, maximum likelihood-type estimation of center. Huber’s M-Estimator, the median, or other robust statistic, is preferred to the average when examining time served due to the skewed nature of the variable; the average has a tendency to produce greatly inflated values.


[2] Starting in 2008, the cohort includes MA DOC inmates released from county, federal and out of state facilities. In 2010, there were 37 DOC inmates released to the street from non-DOC facilities.