(Reuters Health) - Body-camera footage from Oakland, California police officers shows the officers spoke more respectfully to white drivers than black drivers during routine traffic stops, researchers say.
The study, the first systematic analysis of police body-camera footage, found subtle but widespread racial disparities in officers’ language.
“Our findings highlight that, on the whole, police interactions with black community members are more fraught than their interactions with white community members,” said Jennifer Eberhardt, co-author of the study and professor of psychology at Stanford University in California, in a press release.
“Words are power,” Oakland Mayor Libby Schaaf said in a statement. “And this study shows that the words police officers use are consequential.”
She pledged to work to end racial differences in Oakland policing.
Transcripts of 981 stops conducted by 245 Oakland officers in April 2014 showed that police were more likely to call white drivers “sir,” or “ma’am,” or to address them by a courtesy title and their last name, while officers were more likely to address black drivers by their first name or call them “bro,” “dude” or “bud.”
The racial disparities persisted even after researchers controlled for the race of the officer, the location and the outcome of the stop and the severity of the infraction.
Officers were 57 percent more likely to offer an apology, to thank or otherwise speak in what is considered a respectful way to white drivers than blacks, according to the report in the Proceedings of the National Academy of Sciences.
On the other hand, officers were 61 percent more likely to address black residents less respectfully; for example, they were more likely to order blacks to keep their hands on the wheel.
“To be clear: There was no swearing,” Dan Jurafsky, a study co-author and Stanford professor of linguistics and of computer science, said in a statement. “These were well-behaved officers. But the many small differences in how they spoke with community members added up to pervasive racial disparities.”
The Oakland police department is the nation’s first law-enforcement agency to allow a university to examine body-worn camera footage of vehicle stops. The racially diverse Bay Area city of about 420,000 was a pioneer of police body cameras in 2010.
Supporters of police body cameras, worn now in major cities throughout the U.S, say the footage can help avert or resolve cases of police misconduct.
Lead author Rob Voigt, a Stanford linguistics doctoral student, told Reuters Health in an email that the study shows the footage also offers possible insight into everyday police-community relations.
“Police departments can use these tools not only to diagnose problems in police-community relations but also to develop solutions,” he said.
"Although this study focuses on traffic stops, the findings speak to a known issue about policing and racial bias,” said Dr. Gary Slutkin, founder of Cure Violence at the University of Illinois at Chicago School of Public Health.
“Everyone has biases, but because police have so much power over citizens, including to arrest, charge and even use a gun, these biases do cause harm,” Slutkin, who was not involved in the study, said in an email.
Every routine traffic stop is “an opportunity to build or erode public trust in the police,” the study authors write.
Without knowing the race or gender of the officers or the stopped motorists, 70 undergraduate students rated officers’ transcribed utterances based on their level of respect, politeness and friendliness.
Researchers then created a computational linguistic model of how speakers show respect, including apologies and commands, and designed software to identify words and phrases in the body-camera footage transcripts. Investigators employed the software to examine the remaining transcripts.
“The racial disparities in officer respect are clear and consistent, yet the causes of these disparities are less clear,” the authors write.
“It is certainly possible that some of these disparities are prompted by the language and behavior of the community members themselves, particularly as historical tensions in Oakland and preexisting beliefs about the legitimacy of the police may induce fear, anger, or stereotype threat,” they write. “However, community member speech cannot be the sole cause of these disparities.”
Police encounters tend to be stressful, and the study highlights the need for community interventions, like mental health and substance-abuse prevention programs, to try to reduce residents’ encounters with law enforcement, Slutkin said.
SOURCE: bit.ly/2sfVbGH Proceedings of the National Academy of Sciences, June 5, 2017.