Originally posted at Voice of San Diego. By Liam Dillon. Eleven years ago, researchers examining racial data from San Diego police traffic stops found officers were more likely to pull over black and Hispanic drivers than whites. Then they ran into some problems. Too many officers had ignored the department’s policy of gathering racial information on their traffic stops, an issue that only has gotten worse recently. That alone, the researchers said, made it nearly impossible to draw conclusions about police behavior. But even if they had gotten all the data, the researchers faced another headache. No one had figured out how data alone could prove whether police officers racially profiled. The data showed San Diego police had pulled over more black and Hispanic drivers, but more criminal suspects were black and Hispanic, too. “This alternative analysis does not prove that vehicle stops in San Diego are fair for all groups,” the researchers wrote in their report, “but it does demonstrate that they may not be unfair.” The inconclusiveness speaks to something that hasn’t gone away in the decade since racial data collection for traffic stops became commonplace in police departments. Data alone rarely, if ever, reveals definitively whether police engage in racial profiling. Still, criminal justice experts contend gathering the information is crucial to monitoring police actions. SDPD Chief William Lansdowne recently recommitted the department to its racial data collection policy for traffic stops. The usefulness of the exercise will come down to how seriously the department takes it.

Why Data Collection Matters

One high-profile situation shows that data can provide a firm foundation for allegations of racial bias. U.S. District Judge Shira Scheindlin ruled recently that the New York City Police Department’s practice of stopping and frisking pedestrians was unconstitutional. She used data to make up her mind, relying heavily on an analysis from Columbia Law School criminologist Jeffrey Fagan. Among other findings, Fagan learned NYPD officers stopped blacks and Hispanics at higher rates than whites even after accounting for the greater likelihood those minority populations lived in high-crime areas. Fagan told VOSD that the judge couldn’t have determined that stop and frisk was racially biased if the data didn’t exist. “I think it’s inexcusable for a police department to say they’re not going to collect the data,” Fagan said. Data collection’s value goes beyond offering evidence of racial bias, say Fagan and other experts. The data allow departments to move racial profiling discussions from anecdotes to numbers. Police officials could use the data to identify officers who might be showing signs of bias by comparing officers on the same shifts. Data could even be used to combat racial profiling allegations. SDPD officials have reminded officers over the years about the data collection policy, saying the numbers were meant to combat community perceptions that profiling existed. Officers just haven’t followed the policy. “It seems to me that Chief Lansdowne’s claims about the absence of racial profiling and the strong relationship between minority communities and the police department would be made much stronger if there were five or 10 years of data to support this claim,” said Joshua Chanin, a public affairs professor at San Diego State University. Studies also have shown that traffic stops represent the most frequent contact between police and the general public. Keeping data over time could allow the department to see trends in who police officers are pulling over and why they’re doing it.  Citizens, experts said, also should want this information. “I think citizens have a right to know what their police departments are doing, especially with respect to the awesome power of the state to deny people their liberty,” Fagan said.

What Data Collection Can’t Prove

I’ll let SDPD patrol officer Tom Bostedt lead off the case against racial data collection. Bostedt, who also serves on the board of the police union, jumped into a Twitter conversation on the issue with me and local consultant Benjamin Bosanac.

@dillonliam @BPBosanac Millions of $$ spent by agencies statewide with no evidence of anything and data inconclusive at best. — Tom Bostedt (@SD4116) January 7, 2014

Bostedt’s point is that police departments have spent a lot of effort gathering demographic information on their traffic stops, but the data hasn’t proven much. It’s easy for data to show disparities in who officers pull over, like the early report in San Diego did. The challenge is determining whether those disparities reveal police bias. Poorer and minority areas tend to have higher crime rates and a greater police presence, for instance, which could help explain why more minorities might be stopped. Controlling for the numerous factors other than race that could lead to such disparities takes time and resources. Fagan, the Columbia criminologist, said he needed two years to analyze the NYPD stop data and write his report. Data can be misinterpreted, too. In an early federal study on traffic stop data collection, Lansdowne’s experience when he was police chief in San Jose served as a cautionary tale. In 1999, Lansdowne announced San Jose would be among the first big departments to voluntarily gather demographic information on traffic stops like San Diego. His first annual report showed minor disparities between the rate Hispanics were pulled over and their citywide population, and some media and civil rights groups immediately took this to mean the department profiled. The study called this kind of comparison overly simplistic and irresponsible. Some police chiefs expressed reluctance to gather demographics on traffic stops after Lansdowne’s experience. Fewer police departments collect data now than they did five years ago because departments aren’t sure what to do with the numbers, said Jack McDevitt, the director of Northeastern University’s Institute on Race and Justice. Some researchers believe other ways of combating racial profiling are more effective. Lorie Fridell, a criminologist at the University of South Florida, wrote a book analyzing racial traffic stop data 10 years ago. Fridell now advocates for a police training program that focuses on managing officers’ unconscious racial biases. When data collection for racial profiling first came into vogue, experts thought the information would yield more definitive results than experience has shown, she said. “If a chief came to me and said, ‘I have resources to implement science-based training or collect data,’ the choice would be easy for me,” Fridell said. “I would do the training.”

The Bottom Line

At the very least, researchers believe racial data collection on traffic stops can be a tool to track potential police bias, and some believe data collection is essential. So far, Lansdowne hasn’t said much about what he plans to do with the information once he has it. Even though San Diego was one of the pioneers among big departments in collecting data, the city’s history isn’t great. Many officers ignored the data policy as far back as 2001, a time when the department was receiving lots of positive attention for its pledge to gather the information. Bostedt’s comments show that not all officers believe there’s value in it. And Lansdowne told us he wouldn’t commit to collecting the data any longer than a year.