Incarceration serves to remove offenders from a community, but also creates hardships on families, including the loss of an income or a caregiver, in addition to long-term effects on mental health for all involved. After incarceration, people often encounter challenges in obtaining meaningful employment, leading to reductions in long-term productivity, recidivism and widespread effects on a community's social, health and educational systems. Disparities in this rate by race or ethnicity can highlight structural differences in how communities are affected and treated by the public safety and criminal justice system.

In 2018, MetroWest had incarceration rates of 31 for every 10,000 Hispanic or Latino residents, 38 for black or African American residents, 8 for Native American residents, 7 for white residents, and 4 for Asian residents. In other words, the rate for Hispanic residents was more than 4 times higher than that of white residents, and among African Americans, the rate was more than 5 times higher than white residents. Statewide incarceration rates were substantially higher for African Americans (60) and Hispanic residents (49), somewhat higher among white residents (13), similar for Asian residents, and a bit higher for Native American residents (13).

While the region's incarceration rates have fluctuated year-to-year, the overall trend since 2000 is a decline in rates for African American, Hispanic and Native American residents, while the relatively low rates among white and Asian residents have decreased slightly.

Among the region's counties, Worcester had the highest incarceration rates for all racial and ethnic groups, but especially African American (56) and Hispanic (52) residents. Norfolk had the lowest rate for Hispanic residents (13), while Middlesex had the lowest for Black or African American residents (29).

Scholars have tied numerous factors to disparities in incarceration, including racialized stereotypes, policies and practices and community conditions. Stereotypes that portray Black and Latino people, especially males, as inherently dangerous, criminal, and violent lay the foundation for police surveillance and disparate and harsher treatment by the criminal justice system. Communities of color are more likely to be under surveillance and policies such as stop and frisk perpetuate increased police contact. Punitive drug laws have had disproportionate impact on Black and Latino communities. Even though Blacks and whites have similar rates of drug use, Black people are more likely to be arrested and experience harsher sentences. In general, whites experience less harsh sentenced when convicted of similar crimes as Black and Latinos. Given economic disparities, people of color are less likely to experience pre-trial release after arrest. The concentration of Black and Latino communities in highly segregated communities with limited economic opportunities and ineffective schools may also foster crime involvement.

National data for subgroups is not available.