A new study reveals a long-suspected but previously-unproven truth in Indianapolis: Most opioid overdose deaths occur in just 5 percent of the city. And those are the same areas most wracked by violence, such as robberies and shootings.

The study also provides preliminary evidence that a national public health epidemic — the opioid crisis — may be fueling Indianapolis’ growing problem of homicides in recent years.

“Surely this massive opioid epidemic… is having an impact on the homicide numbers,” said Brad Ray, associate professor at Indiana University-Purdue University Indianapolis and one of the researchers behind the study. “I wish the public could see these two things as potentially associated where these homicides are the result of the opioid epidemic.”

The study does not show that opioid abuse is limited to areas where violent crime occurs. Instead, Ray said, it suggests that people lacking the means for treatment are the ones less likely to survive an overdose.

“Where people have opioid use disorder versus where they die is totally two separate things,” Ray said.

More affluent Hoosiers who overdose, Ray said, may be more likely to call 911, seek addiction treatment or keep naloxone at home.

Ray and two other IUPUI professors — Jeremy G. Carter from the School of Public and Environmental Affairs and George Mohler from the School of Science — created the study that published this month in the Journal of Contemporary Criminal Justice.

They collected Indianapolis Metropolitan Police Department crime data; Indianapolis EMS medical calls; and toxicology data from the Marion County coroner’s office.

Their analysis found that 5 percent of the city accounts for nearly 54 percent of all opioid deaths; nearly 58 percent of heroin and fentanyl-caused overdose deaths; and nearly 65 percent of prescription opioid deaths.

Additionally, these pockets across the city are responsible for about half of all EMS drug overdose calls, including calls for people who overdosed but survived.

Neighborhood problems that foster criminal activity — such as streets of vacant housing or a dearth of job opportunities — are the same problems that contribute to overdose deaths, Carter said.

Empty buildings, for example, can be used both for drug-dealing and drug use — outside of the eye of law enforcement and watchful neighbors.

“That vacant home provides a mechanism for crime to occur,” Carter said.

The study’s findings, researchers say, suggest agencies and community leaders could focus their limited resources in these areas to better alleviate the problems.

And there are implications for IMPD, which has shifted its policing strategy in recent years to efforts meant to reverse a yearslong trend of ballooning homicides.

IMPD Chief Bryan Roach said he was not surprised to learn of the study’s findings on Monday. But what he believed anecdotally is now backed by research, he said.

For a department that routinely partners with other public agencies and nonprofit groups, it’s crucial for IMPD to let such data guide its response to public safety concerns.

“Our resources are limited,” Roach said. “And social service resources are limited.”

The study does not identify which areas of Indianapolis are experiencing the overlap between overdose deaths and violence. But maps included in the study illustrate the problem appears to be most pronounced in neighborhoods around Downtown.

Now that the researchers have discovered the overlap, they hope to meet with Roach and other city leaders to dive deeper into the data and discuss potential solutions.

Once IMPD learns the specific areas effected, Roach said he’ll ask for help from nonprofits in those neighborhoods who have been awarded crime prevention grants.

“I think there’s an opportunity there to be more unified,” Roach said.