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Reform Boston’s gang database, don’t dismantle it

On an annual basis, gang violence generates about half of the homicides in Boston, and gang members are involved in roughly two-thirds of nonfatal shootings. Most of the violence is due to a small number of individuals, typically gang members.

Guns seized from gang members are shown during a press conference at Moakley Federal Courthouse in Boston in December 2019.David L. Ryan/Globe Staff/file

In 2021 there were 40 homicides in Boston, close to a historic low. This occurred in a context where homicide rates nationally rose by 30 percent in 2020, the largest single-year increase ever, and have continued to rise through 2021, with many cities reaching historically high numbers of homicides. Might Boston be doing something right?

On an annual basis, gang violence generates about half of the homicides in Boston, and gang members are involved in roughly two-thirds of nonfatal shootings. In Boston and other cities, most of the violence is due to a small number of individuals, typically gang members. In the last five years, all gang-related homicides have involved individuals of color. Gang violence is clearly an ongoing problem that needs to be addressed by the city.


Gang databases are a critical element of a policing strategy known as “focused deterrence,” and suggestions that the database be eliminated are misguided. The goal of focused deterrence is to focus on high-risk individuals and stop further violence through a strategic blend of law enforcement, social services, and community-based action. For example, after a gang shooting, officers and their partners need to identify gang members who are likely to retaliate. Knowing which gangs are involved, and their membership, is necessary to do this, and a gang database enables this.

The Boston Police Department’s Youth Violence Strike Force, supported by the Boston Regional Intelligence Center, and its focused deterrence strategy in particular, represents a central part of the city’s efforts to prevent gang-involved gun violence. The gang database is a key component of this effort. Analysts in the Boston Regional Intelligence Center support the database on a part-time basis, at a cost of about $150,000 a year.

Focused deterrence programs have been shown to be highly effective in many cities. Two rigorous evaluations of focused deterrence in Boston, one conducted during the mid-1990s and the other during the mid-2000s, show that this approach resulted in significant reductions in gang-related gun violence.


People living in high-crime neighborhoods, particularly young men of color, bear a disproportionate policing burden. Still, most youth living in these neighborhoods are innocent of any crime. They, however, are far more likely to be stopped and questioned by police than youth living in more affluent neighborhoods, certainly an infringement of their civil liberties, as well as more generally a detriment to police-community relations. A key question is whether ending the gang database would lessen this undeserved burden or increase it.

We know of no academic study that has examined this question. Related academic work, though, is suggestive. In 2017, economists Amanda Agan and Sonja Starr examined the effect of “banning the box,” which restricts employers from asking job applicants about their criminal histories. They did an audit study of fictitious Black and white individuals applying online for jobs. Prior to the implementation of banning the box, they found that employers who asked about a person’s criminal history were 63 percent more likely to call applicants with no record. However, they found that prior to banning the box, white applicants received 7 percent more callbacks than Black applicants. This gap increased to 43 percent after its implementation. In short, when employers were not able to ask about criminal history, they were far more likely to discriminate against Black people. Clearly, without additional information, employers showed an increased bias against Black applicants.


Prior to the mid-1990s, Boston did not have an effective deterrence strategy. The result was two-fold: with the proliferation of crack cocaine, Boston, like other cities, experienced a period of uncontrolled gang violence; Black youth were indiscriminately and frequently stopped by police. The most famous example was after the Carol Stuart murder in 1989, when young Black men, no matter who they were or their circumstances, were, in the language of the police, “tipped upside down.” The police had no idea who might have been responsible. They were searching for a Black male, based on a description by Stuart’s husband, who himself later turned out to be her killer.

Does the gang database need to be reformed? Certainly. The purpose of a focused deterrence strategy is, as the name indicates, to focus on the number of individuals involved in gun violence and prevent them from committing further shootings. The fact that 10-11 percent of Black males ages 18 to 34 are in the gang database suggests that it is casting far too wide a net.

A more focused and targeted database is needed. Based on prior academic efforts to create a census of gangs and gang members, the gang database should be about half its current size — 1,700 or so individuals, as opposed to the current 3,406. This would increase police efficiency, lowering homicide rates even further as well as lessening the civil liberties burden — the exact purpose of a focused deterrence approach. As Boston’s history suggests, eliminating the gang database could well result in the opposite effect. Police will still assume that many individuals are gangs members, and, correct or not, treat them as such.


Christopher Winship is a professor of sociology at Harvard University. Anthony A. Braga is a professor of criminology and director of the Crime and Justice Policy Lab at the University of Pennsylvania.