A 16-year-old was fatally shot Friday April 19, 2019 inside a rowhouse in the Parkview neighborhood of Northwest Washington, according to D.C. police. (Clarence Williams/TWP)

Police and other officials trying to understand the District’s rising homicide count have attributed it in part to shootings becoming more lethal, and now they say they may know why. A new study found that more victims are being struck by multiple bullets.

The report by the D.C. Office of the Chief Medical Examiner found that 57 people killed in shootings in the city in 2017 were struck multiple times. That number rose to 74 last year.

“Instead of single gunshots to the legs, we are seeing gunshot wounds going through the chest and abdomen, and causing multiple injuries,” said Mallory Williams, the chief of the division of trauma and critical care at Howard University Hospital.

District officials have partly blamed easy access to illegal weapons that are then used in crimes such as robberies or to settle personal disputes. Authorities said they are seeing fewer killings over drug turf or neighborhood rivalries.

While authorities already look closely at the backgrounds of suspects, the findings have prompted a new effort to study victims, examining factors including economic status, housing, health care, education and any contacts with social programs and interactions with the criminal justice system.

The District hopes to use these profiles to better understand the underlying causes of gun violence and find ways to curtail it. It is part of Mayor Muriel E. Bowser’s (D) broader efforts to confront the homicide spike on two simultaneous fronts: traditional police enforcement coupled with health-based initiatives.

“We have to be good at both policing and healing,” said Kevin Donahue, the deputy mayor for public safety and justice.

The District said the planned Violence Fatality Review Committee could start work in a few months.

Roger Mitchell Jr., the District’s chief medical examiner, said he hopes a better understanding of victims’ backgrounds will help officials “discuss where policies can be improved to decrease fatalities due to violence.” He said the group will look at each victim to see “where this person came into contact with the system and was there an opportunity for the system to have engaged differently or better, and might that have led to a different outcome.”

Killings in the District rose significantly in 2018. That trend is continuing, with a slight rise in homicides so far this year compared to the same period last year.

And although the percentage of victims hit by several bullets went down slightly in 2018 compared with 2017, Mitchell said he is most concerned by the overall number of fatalities. He noted that victims of fatal shootings suffered an average of 4.3 wounds last year, up from 3.8 in 2017.

The grim bottom line, Mitchell said, is “more people are rolling through our doors with multiple gunshot wounds.” The research also found that when victims of fatal shootings are struck by just one bullet, more of those wounds are to the head.

The study builds on findings from 2018 that showed more people are using guns in crimes such as robberies and assaults, leading to more deadly outcomes. They have also said there are more large-caliber guns holding large amounts of ammunition.

The apparent shift in motives has led to new challenges for authorities trying to stop the violence. The District employs programs to identify pockets of tension, including “Violence Interrupters” who immerse themselves in neighborhoods to learn about grievances and talk of retaliation.

But disputes between people who know each other, Donahue said, “are more difficult to anticipate.”

Donahue said an initiative to fund a nonprofit organization to open three trauma counseling sessions in areas hard hit by violence could help identify and resolve some of those personal conflicts.

Mitchell said he has already shifted the focus of the medical examiner’s bereavement center to calm people angry over killings. “Grief is a form of trauma,” he said, “and people who have unresolved grief have a higher propensity toward acting out in violence behavior.”

Williams, the trauma chief at Howard University Hospital, said the review board could help his doctors as well as city agencies better understand why the violence is happening, and treat it as a public health crisis. He cited one challenge facing the District — gentrification — that is rapidly altering the landscape of many neighborhoods, pushing out residents, and shifting crime patterns that can create tension.

“D.C. is a dynamic city, and it’s going through an evolution in terms of construction and an increase in population,” Williams said. “What we have to focus on is how we measure the community’s well-being, in all our wards. This has to be front and center in the public policy conversation if we’re going to effectively address violent crime.”

John D. Harden contributed to this report.