A white Nashville officer is under intense scrutiny after fatally shooting a black man while he was fleeing, allegedly with a gun.
Now, as Officer Andrew Delke faces a homicide charge, one Vanderbilt doctoral candidate has crunched more than a year of his traffic stop data, which suggests some trends in his style of policing.
Vanderbilt sociologist Peter Vielehr worked on the high-profile Driving While Black report, which used Metro Police data to show that black drivers were being stopped far more often than white drivers.
Activists cited the report as proof of racial profiling and bias. While Nashville's police chief derided the study, calling it "morally disingenuous."
Vielehr doesn't side with either. He says data shows action, not intention.
"We can show that there is a really substantial racial disparity between black and white drivers in Nashville," Vielehr said. "What we can't show is that officers are intentionally targeting black drivers."
Which is why he was initially reluctant to do a quick analysis of Delke’s traffic stops: Those alone don't tell much of a story. But last week, after gathering more department-wide data as a comparison, he published the findings on his website.
More Stops Than Average
Vielehr looked at every traffic stop Delke made and compared those figures to other officers who worked in the same zones. To make more accurate determinations, Vielehr said he counted only areas of the city where Delke made more than 10 stops, and only compared him to other officers in those zones who also made more than 10 stops.
"I find that in the majority of zones that he is patrolling he is making more stops of black drivers than the average officer," Vielehr said.
More specifically, Delke was above the average of all officers in nine out of the 10 zones Vielehr analyzed, and often by a large margin.
Also, according to the data, Delke searched the black drivers he stopped nearly three times the rate of his fellow officers across the city—10.7 percent compared to 3.8 percent. In the end, Delke's searches didn't turn up much more evidence than the average officer. He found evidence 33 percent of his searches, compared to the average 26.5 percent for other officers.
Preventing An 'Adverse Encounter'
All of this doesn't indicate Delke shot Daniel Hambrick because of his race. But Vielehr said the data can suggest that Delke may have had a more aggressive style of policing than many of his colleagues.
"In general, Officer Delke's traffic stops and vehicle searches paint a picture of an officer who stopped and searched black drivers more aggressively than his peers," Vielehr writes in his report.
And Vielehr believes that mining this kind of data can present an opportunity for police departments to take corrective action—administer extra training or switch up an officer's daily tasks.
"It probably should have had increased attention before he had an adverse encounter," Vielehr said of Delke's stop and search rates.
When asked for comment, Delke's attorney, David Raybin, said this kind of study is "fundamentally flawed" because Delke's assignments changed over time, which could have impacted who he interacted with. Most recently, he was on the city's newly formed Juvenile Crime Task Force.
"The job task of the officers will impact your numbers," Raybin said in an email.
However, the Nashville Police Department is already doing a version of this kind of data analysis. Kris Mumford, a spokeswoman for the department, says it was deployed in 2016.
The last round of citations based on data collected from the first three months of the year, she said, although she could not give details about what statistics the data was based on. Fifty letters were sent to supervisors and cited officers who were "outliers" in some sort of behavior or task. Of those 50, Mumford said, eight employees received “some form of follow up."
She couldn't say whether Delke was among that group, adding that any interventions are confidential unless they result in formal discipline.