A 10-month study of traffic stops in Massachusetts found no evidence of racial disparity in which drivers police chose to pull over, but determined that drivers of color were more likely to be subjected to searches and had a higher chance of receiving a criminal citation than white drivers, according to a new report.
Black and Hispanic drivers were least likely to be given a warning after being pulled over and more likely to be arrested compared with white drivers, according to the 415-page report, which was released late Monday afternoon by the state’s Department of Public Safety and Security.
A spokesman for the department said no one there was available to discuss the report on Monday.
The study looked at traffic stops from February to December 2020 and analyzed data from State Police and local departments that conducted 100 or more stops — about 280 of the 350 law enforcement agencies in the state, officials said in a statement.
Researchers from Salem State University and Worcester State University analyzed the data using a method called the “Veil of Darkness,” which “compares stops made in darkness to those made in daylight, based on the logic that police officers are less likely to be able to determine a driver’s race at night than during the day,” the statement said.
“The statewide VoD analysis found no support for patterns of racial disparity in traffic stops,” the statement read. “According to the report, non-white motorists are 36% less likely to be stopped in daylight (when they could potentially be seen and racially profiled for a stop) than in darkness.”
But drivers of color who were stopped were more likely to be searched, criminally cited, or arrested than white drivers were, according to the report.
Researchers also found that the data from the Hadley Police Department, Ludlow Police Department, and State Police Troop H-3 in Foxborough indicated that officers were pulling over drivers of color at a higher rate during the day than at night, according to the report.
In a summary of the report, researchers said the findings do not prove that officers with those departments were engaged in racial profiling.
“This baseline research should serve as a starting point for deeper understanding, continued discussions, and further reflection,” Gina Curcio, a researcher at Salem State, said in the statement. “We caution that our findings do not confirm racial profiling and any incidents of statistical significance could have a variety of explanations other than officer bias.”
The study stems from the hands-free driving law the Legislature passed in 2019, which included a requirement for an annual analysis and public report on police traffic stops across the state, the office’s statement said.
The data were drawn from traffic citations collected by the Registry of Motor Vehicles and provided to the researchers, who could then analyze who was being stopped based on age, gender, and race. The study also looked at the date, time, and location of the traffic stop, as well as whether it resulted in a warning, citation, or arrest, or if the police searched the person’s car.
Law enforcement agencies across the state made 425,702 stops during the 10-month study, officials said. About 60 percent of those stops were made by municipal police, and 40 percent were made by State Police.
Among the drivers stopped, 65 percent were male, 34 percent were female, and about 1 percent were gender nonbinary, the office’s statement said. About 39 percent of the drivers were under 30, the statement said.
White drivers accounted for 65 percent of traffic stops, Black drivers made up about 16 percent, and about 15 percent were Hispanic drivers, the statement said. About 4 percent were either Asian, Asian Pacific, American Indian, Middle Eastern, or Pacific Islander, the statement said.
In Boston, police made 25,029 stops over the 10-month period, with 44.6 percent of those stops involving Black drivers, while 32.4 percent involved white motorists, according to the report.
For Black drivers in Boston, 83.6 percent of stops ended in police giving the driver a warning, 11.3 percent ended with a civil citation, 4.2 percent with a criminal citation, and 0.9 percent ended in arrest, according to the report. Hispanic drivers were given a warning in about 81 percent of stops, a civil citation in 15.2 percent of stops, a criminal charge in 3.4 percent of stops, and were arrested in 0.3 percent of stops.
About 88.7 percent of white drivers were let off with a warning, 9.4 percent received a civil charge, 1.6 percent received a criminal charge, and 0.2 percent were arrested, according to the report.
The Executive Office of Public Safety and Security will host three virtual public hearings to discuss the analysis and take public testimony on the report. Those hearings are scheduled for Feb. 28 from 10 a.m. to 2 p.m., March 1 from 3:30 p.m. to 5:30 p.m., and March 2 from 1 p.m. to 3 p.m.