Force Science News #266:

Cops hesitate more, err less when shooting black suspects, study finds


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I. Cops hesitate more, err less when shooting black suspects, study finds

II. Important new links to Force Science findings

III. Chicago's OIS investigators get special training in Force Science

IV. Upcoming lecture on active shooter threats & room entry tactics


I. Cops hesitate more, err less when shooting black suspects, study finds


With the turmoil in Ferguson (MO) the latest example, activists and many reporters would have us believe that police officers are prejudicially trigger happy when dealing with black suspects.


But a scientific study from Washington State University-Spokane suggests just the opposite.


In truth, according to findings from the research team's innovative experiments:


• Officers were less likely to erroneously shoot unarmed black suspects than they were unarmed whites--25 times less likely, in fact;


• And officers hesitated significantly longer before shooting armed suspects who were black, compared to armed subjects who were white or Hispanic.


"In sum," writes Dr. Lois James, a research assistant professor with the university's Department of Criminal Justice and Criminology who headed the study, "this research found that participants displayed significant bias favoring Black suspects" in their shooting decisions.


OLD VIEW. In the past, based largely on incident report analyses and simplistic laboratory experiments, various researchers have concluded that in making deadly force decisions police are strongly influenced by the race or ethnicity of suspects, "independent of criminality."


In the 1970s, this perspective was memorably captured in one researcher's statement that "the police have one trigger finger for whites and another for blacks." Another claimed that the "disproportionate" number of police shootings of blacks (according to DOJ figures, they are four times more likely to be shot by police than whites) "strongly suggests racial discrimination on a national basis" in law enforcement.


But James points out that it is difficult if not impossible to ferret out racial bias as a decisive factor in shootings from the incomplete and occasionally questionably accurate information included in most incident reports. And the laboratory experiments suggesting bias, she says, commonly "bear almost no resemblance" to real-life deadly force encounters.


For example, a typical research method has involved subjects sitting before a computer and viewing flash pictures of black and white "suspects" paired with weapons or "neutral objects" such as wallets or cell phones. The subjects must respond to these images by pressing "shoot" or "don't shoot" buttons. Racial bias is then inferred by whether participants are "consistently quicker to shoot armed suspects of a particular race" and by whether decision errors tend to be greater for one race than for the other.


This process lacks what James calls "external validity"; that is, it doesn't come close to reflecting real-world circumstances, and thus its conclusions are of limited value. "[T]he complex process involved" in deciding to shoot or not shoot and then actually firing a gun is "dramatically different" from the simple reflex of pressing a button, she writes.


Her study involved a more sophisticated, "immersive" approach.


ENHANCED TESTING. Along with civilians and military personnel who were tested independently, 36 patrol officers and deputies from the Spokane area, all of them white and most of them male, were selected as volunteer subjects for her research. They ranged in age from 31 to 43 and had at least five years on the job.


Armed with a Glock 21 modified to fire a laser beam, the officers one at a time were exposed to a series of at least 10 "highly realistic and arousing" scenarios in a high-definition deadly force judgment and decision-making simulator in WSU's Simulated Hazardous Operational Tasks laboratory. The equipment permitted precise determination of shot placement and millisecond measurement of shot timing after a threat appeared.


The life-sized scenarios were randomly screened from a pool of 60 one- to two-minute episodes based on actual encounters in which officers have been killed or assaulted. They were filmed in "naturalistic" environments and included disturbance calls, arrest situations, crimes in progress, suspicious person investigations, and traffic stops--the biggest killers of cops. They ranged in "situational difficulty" from "intermediate" to "journeyman," depending on variables such as the number of people involved, the speed at which action unfolds, and suspect demeanor, intoxication, and deceptive behavior.


Black, white, and Hispanic suspects appeared in the scenarios proportional to their involvement in actual attacks on officers, as compiled in FBI statistics. Suspects were unarmed in about a third of the scenarios.


The key responses that the researchers tested were reaction time and shooting "errors" (in this case, shooting unarmed individuals or failing to shoot armed suspects).


James emphasizes that the officer participants had no reason to believe they were being tested for racial or ethnic bias. The issue of suspect race or ethnicity was not raised during the officers' preparation, and no Ferguson-like, racially charged event was recently in the news that might have overly sensitized them to that concern.


UNEXPECTED RESULTS. Given the prevailing stereotype that cops are unduly harsh toward black suspects, James acknowledges that the outcome of the experiments was "unexpected."


• Reaction time. Her findings reveal that officers took "significantly longer" before they shot black suspects than white suspects. Civilians and soldiers in the study also took longer to shoot blacks, but the hesitation by officers was roughly twice as long as that of the civilians. The delay before shooting was particularly noticeable in the most complex scenarios.


In contrast, there was "no significant difference in reaction time between shooting Hispanic suspects and White suspects," James reports.


"Our primary finding that participants were more hesitant to shoot Black suspects than White or Hispanic suspects is in direct contrast to prior experimental findings that participants are significantly quicker to shoot Black suspects," she writes.


• Decision errors. Where officers made errors in James's study, they were "less likely to shoot unarmed Black suspects than unarmed White suspects," she writes. Indeed, "we calculated that participants were 25 times less likely to shoot unarmed Black suspects than they were to shoot unarmed White suspects." Again, this was a significantly greater multiple than was recorded for other groups in the study.


Unarmed suspects were most likely to be shot in journeyman scenarios (the most difficult), and there was "no significant difference between the likelihood of shooting unarmed Hispanic suspects and unarmed White suspects," the researchers found.


Moreover, the officers did not fail to shoot armed white suspects any more frequently than they failed to shoot threatening suspects who were black or Hispanic.


"These findings are also in direct contrast to [earlier researchers] who found that participants were more likely to shoot unarmed Black suspects and fail to shoot armed White suspects," James noted.


These results revealed that racial bias did exist in the officers' reactions to the scenarios, James writes--"but in the opposite direction that would be expected from prior experimental studies." Her tests "showed significant evidence of bias favoring Black suspects, rather than discriminating against them."


A "potential explanation," she speculates, may be a "behavioral 'counter-bias' " or "administrative effect"; that is, an extra caution by officers against impulsive reactions to black suspects because of "real-world concern over discipline, liability, or public disapproval."


[Although not relevant to the researchers' primary concerns, James' team also recorded something that was not surprising: Compared to the civilian volunteers, "police and military participants had better shooting accuracy, fired faster follow-on shots, were far more interactive with the scenarios (for example, shouting at suspects: 'drop your weapon or I will shoot!'), and had superior command presence...."]


FUTURE RESEARCH. James considers her research to be a pilot study and as such she plans to expand it numerically and geographically before feeling confident that the findings can be extrapolated to sworn law enforcement generally. In work that is already underway, she hopes among other things to investigate whether this finding is replicated across larger and more diverse law enforcement samples, and if so, to "determine whether bias favoring Black suspects is a consequence of administrative measures (e.g., education, training, policies, and laws), and identify the cognitive processes that underlie this phenomenon."


Meanwhile, the existing study, published in print last year under the title "Results from experimental trials testing participant responses to White, Hispanic and Black suspects in high-fidelity deadly force judgment and decision-making simulations," can be accessed in full for a fee at the website of the Journal of Experimental Criminology. Click here to go there.


James can be reached at: Joining her in conducting the study were two other WSU PhDs, Dr. Bryan Vila and Dr. Kenn Daratha.


II. Important new links to Force Science findings


Two links to new reports on Force Science research:


• A new study by the Force Science Institute documents that officers may be "significantly" impeded in trying to move quickly away from threats because of the weight of their duty-belt gear and protective equipment.


Subjecting a pool of law enforcement students to a series of "maximal-effort" sprint tests, researchers led by FSI's executive director Dr. Bill Lewinski found that adding about 20 lbs. to the recruits to simulate a typically outfitted duty belt and ballistic vest resulted in "significant detrimental effects on officer velocity and acceleration" in taking the critical first six strides away from danger.


"This impediment can impact how quickly an officer can move to cover from a shooting attack, get out of the way of an oncoming vehicle, or maneuver effectively during a close-quarters physical encounter," Lewinski told Force Science News. "Because our test subjects were young and very fit, the average officer is likely to be even more negatively affected than they were." The answer, Lewinski suggests: a career-long commitment to lower-body strength and power training and maintenance, as well as intensive agility training.


A full report of the study, titled "The influence of officer equipment and protection on short sprinting performance," is available online free of charge until Nov. 8. Click here to get a copy before that date. It will be published in print form next year in the journal Applied Ergonomics.


• Dr. Lewinski's presentation last month on decision-making under stress before the international Risky Business medical conference in London is now available online. For free viewing of the 27-minute lecture, CLICK HERE or go to:


III. Chicago's OIS investigators get special training in Force Science


One of the nation's premier force-review agencies has turned to Force Science training to help its investigators and supervisors to better understand the human dynamics of officer-involved shootings.


Chicago's Independent Police Review Authority (IPRA) recently hosted an intensive two-day session with Dr. Bill Lewinski and instructor Chris Butler of the Force Science Institute for 60 of IPRA's personnel, plus about 30 invited representatives from law enforcement agencies that included the FBI, the DEA, and the Illinois State Police.


An independent municipal body, the IPRA investigates all OISs and Taser discharges, excessive force allegations, domestic violence cases, and other force-related complaints involving Chicago PD officers, determining what happened in about 45-65 shootings alone each year.


The breadth of its investigative powers and responsibilities is rare among review agencies, according to Chief Administrator Scott Ando. But because only eight of its roughly 70 investigators, supervisors and command staff have law enforcement backgrounds, Ando, who himself has logged 33 years in law enforcement, including 28 years with the DEA, thought it was paramount that his investigative staff receive FSI training.


The Force Science team provided what Ando describes as "phenomenal instruction" about the human factors that can influence deadly force encounters, ranging from the decision-making process under stress to the impact of a life threat on memory.


"I've gotten nothing but rave reviews from the people who attended," he says. "The instruction was constantly energetic, entertaining, and thought-provoking. There's no doubt it opened up minds to the possibilities that can happen in a shooting."


His goal now is to start getting his staff trained more extensively in Force Science investigative principles, via the weeklong certification course in Force Science Analysis.


IV. Upcoming lecture on active shooter threats & room entry tactics


This year's special presenter for the annual Lewinski Lecture Series at Minnesota State University-Mankato will be Dr. J. Pete Blair, research director for the Advanced Law Enforcement Rapid Response Training Center (ALERRT) at Texas State University.


Blair will address two principal topics: a review of 14 years of data regarding the danger that active shooter events pose to responding LEOs and the findings of his group's studies of which room entry tactics tend to produce the best balance of speed and accuracy in armed encounters with violent suspects.


To access the recently released FBI study on active shooters that Blair will be referencing, CLICK HERE.


The lecture series was established by Minnesota State in honor of Dr. Bill Lewinski, who spent 28 years on the law enforcement faculty there before retiring to devote full time to the Force Science Institute, which he founded. Each year the university's Center for Applied Research in Law Enforcement, which sponsors the series, selects as a speaker an individual who is "conducting exceptional research and training in criminal justice."


Blair's free presentation will be at 11 AM Oct. 13 in Ostrander Auditorium at MSU's Centennial Student Union. For more information, contact Colleen Clarke, director of the University's law enforcement program, at:


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