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Police officers stand in front of the Philadelphia Police Department Headquarters on Sept. 4, 2020.

Credit: Sukhmani Kaur

A study conducted by Penn criminologist Aaron Chalfin and other researchers showed that increasing the size of police forces results in an increase in arrests for low-level offenses and a decrease in homicides.

Chalfin and his colleagues at Barnard College, the University of California, Los Angeles, and the University of Oregon found that adding 10 to 17 officers to a city’s police force led to one fewer homicide per year, with each additional officer leading to seven to 22 arrests for “quality of life” crimes such as drug possession, loitering, and liquor violations. 

Chalfin was motivated to study the effects of expanding the police presence in the country as the debate surrounding reforming and defunding the police took place, Penn Today reported. 

Of the almost 14,000 murders where the race of the victim was known in 2019, nearly 54% were Black  — though Black people make up 13.4% of the U.S. population. The homicides prevented by the increased police force were also in cases where the victim would have likely been Black, Penn Today reported.

According to Chalfin, the research suggests that expanding police forces could be effective for reducing homicides, however, he told Penn Today that “a portfolio of strategies” is necessary to reduce violence in cities.

Other strategies that have been proven to reduce crime include strengthening community-based organizations and revamping public spaces, indicating the potential to maintain or reduce police forces without seeing upticks in crime, Vox reported. Bolstering local groups could also shift the burden of handling drug addiction and mental health crises away from the police to people who are better equipped to handle public health issues. 

In 2019, the FBI recorded 16,425 murders in the United States, equivalent to about five homicides per every 100,000 people. 

America saw a 30% increase in homicides in 2020, with Philadelphia recording a near-record high of 499 murders. In order to curb this spike in violence, the city was chosen to participate in the National Public Safety Partnership program — which provides federal funding to the Philadelphia Police for training and assistance with gun violence, community engagement, and crime analysis.

Philadelphia’s Office of Violence Prevention and City Council distributed $4.8 million for community programs in response to the rise in crime, with a focus on schools where children have been at risk. 

Chalkbeat Philadelphia reported that Mayor Jim Kenney said one strategy is not enough to respond to heightened levels of violence in the city.

"We will continue to do everything possible to protect our communities and to work with city leaders and law enforcement to promote public safety,” he said on Nov. 1.