Force Science News #250:

Unique new study confirms memory discrepancies after OISs

In this issue:


I. Unique new study confirms memory discrepancies after OISs

II. Cop's estimates become sticking point in bizarre shooting

III. Our readers write on active shooter mindset & ER assessments


I. Unique new study confirms memory discrepancies after OISs


New research findings by the Force Science Institute provide fresh evidence that an officer's ability to accurately remember potentially important details may be significantly compromised after a shooting.


"In certain circumstances, these findings may help investigators account for memory discrepancies that might otherwise be interpreted as an officer's willful effort to be misleading," FSI's executive director Dr. Bill Lewinski told Force Science News. "This research adds a small but important piece to the growing scientific mosaic of how the human brain reacts to highly stressful, life-threatening events."


The findings have emerged as researchers continue to mine a rich lode of data gathered during a ground-breaking FSI experiment in which LEO volunteers were unexpectedly attacked with Simunition rounds fired by an angry driver during a traffic stop scenario.


Initially, the research team analyzed the subjects' immediate physical responses in an effort to determine what path of movement would most quickly bring the officers to a safe location. [Those findings were reported in FSN #224, transmitted 2/25/13. Click here to read it. See also the detailed report titled "The Influence of Officer Positioning on Movement During a Threatening Traffic-Stop Scenario," which appeared in the journal Law Enforcement Executive Forum and is posted on the Force Science website. You can read it by clicking here.]


Now the team, headed by Lewinski, has studied a subset of the volunteers to see how accurately they were able to remember the precise route they took in their flight to escape the gunfire--one of many details officers may be asked to accurately report on after an OIS.


"Focusing on that level of detail may seem trivial," Lewinski observes, "but in real life it has proved vital for some shooting survivors." In the Force Science certification course, for example, Lewinski recreates the case involving Arizona officer Dan Lovelace, who was charged with murder after a fatal shooting, in part because he misstated where he moved in an effort to dodge a vehicle that was being driven directly at him.


"There was merely six inches of difference between where Officer Lovelace said he moved and where forensic evidence calculated that he actually moved, but it was enough to raise doubt about his credibility and to help wreck his law enforcement career and his life," Lewinski says. [For more information visit the Force Science News Archives at and search for the name, Lovelace.


RECALL TEST. The unique memory component of the traffic stop study involved 24 of the participating officers, sergeants, and detectives--all randomly selected males, ranging in age from 27 to 54, with up to 31 years on the job.


Promptly after they had been "intensely stressed" by being fired on (as confirmed by physiological monitors), each was given a sheet of paper with a diagram of the shooting scene, including the positioning of their patrol car and the suspect vehicle.


During the scenario, most had fled to the rear of the gunman's car in an attempt to escape. Based on their memory of what had just occurred, they were instructed to draw "as accurately as possible" their path of travel from the instant the assailant drew his weapon until they heard the whistle that ended the scenario. They were allowed "as much time as necessary" to complete the drawing.


Later, the research team made meticulous, frame-by-frame computerized analyses, comparing the officers' drawings with digital video recordings of their actual flight paths from danger.


DISCREPANCIES WIDE & LONG. Here's what they found:


1. the officers tended to recall and draw a much tighter curve of travel around the rear of the offender's vehicle than they actually made as they ran to their eventual stopping point, and


2. they thought they ran a significantly longer distance than they actually did.


The fact that memory errors occurred was not surprising to the researchers, based on well-documented studies of brain function under stress. "In a life-or-death confrontation," Lewinski explains, "the brain automatically filters out what it believes to be irrelevant in its laser focus on what is most important--survival. Later, exact details that were subconsciously judged to be extraneous are likely to be impossible to recall with precise accuracy, because they were not imprinted in a person's working memory."


SIGNIFICANCE. The findings from this first-of-its-kind study "demonstrate the amount of error that investigators can likely anticipate when dealing with recalled movement, distance, and location during a high-stress event, such as an OIS," Lewinski says.


"The implications of the study are broader than that, however. After a shooting, officers are commonly asked not only to recall where they moved but where they fired their first round, how they held their firearm, how many rounds were fired, and so on. In the midst of a life threat, they are likely to be acting automatically, without conscious thought, and what they can recall or think they can recall about automatic behavior, if anything, may not reflect what really occurred because it was not recorded in conscious memory. Their overwhelming cognitive focus would have been on saving their life.


"The credibility of officers and witnesses is often challenged because of inaccuracies in their recollections of critical incidents. They are expected to be accurate with incredible precision, and their inability to do so is too often equated with deception. We hope that this study will help in redefining the expectations of memory more realistically."


An academic paper on the study will be submitted to a peer-reviewed journal for publication. We'll advise when that is available.


Meanwhile, read the article below to see how officers' recalled estimations can be challenged in real-world situations.




II. Cop's estimates become sticking point in bizarre shooting


An officer who shot a suspect who had him trapped inside a car that was gathering speed discovered that his inability to accurately estimate measurements afterward became an issue when the case got to an appellate court.


The bizarre situation began about 0200 one Friday when two Anaheim (CA) PD officers narrowly missed colliding with the driver of an old Mazda van who made a sudden, illegal left turn in front of them.


Pulled over, the violator belligerently refused to turn off the ignition, to stop reaching toward areas where a weapon could be concealed, and to reveal what the officers suspected was a plastic baggy of drugs clutched in his hand. As the situation escalated, the officers delivered repeated flashlight and fist blows, and a carotid restraint was attempted through the driver's window--all to no avail.


In desperation, one of the officers, Danon Wyatt, scrambled into the van through the front passenger door. Kneeling on the seat, he punched the suspect in the head and face while his partner hammered the driver with a flashlight, trying to bring him under control.


During the struggle, the driver slapped the gearshift with his right hand and knocked it into drive. According to the officers' statements later, the suspect then "stomped down" on the gas pedal; the van bolted forward with a squeal of tires--and the passenger door slammed shut, trapping Wyatt inside.


Wyatt yelled at the driver to stop and tried to hit the shifter out of gear, but the suspect fought his hand away. Then with the van accelerating forward and without further warning, Wyatt drew his sidearm and shot the suspect in the head. The van smashed into a parked vehicle and stopped. The driver died soon after.


Predictably, relatives filed federal lawsuits against the officers and the city, alleging excessive force. The district court granted summary judgment in favor of the defendants. In appealing to the 9th Circuit Court of Appeals, the plaintiffs' lawyer challenged certain time and distance estimates Wyatt had made after the shooting, in an effort to discredit the officers' version of what had happened and get the case before a jury.


Wyatt had stated that the van had traveled "approximately fifty feet" in "less than ten" and possibly "less than five" seconds and was going about "50 miles per hour" when he shot the driver. As an "unbuckled passenger in a fast-moving vehicle driven by an escaping suspect," he felt he was in immediate and significant threat of death or serious injury.


However, the plaintiff's lawyer argued that "Wyatt's story fails to hold together." By Wyatt's own estimates, the attorney calculated, the van actually had to have been traveling so slowly that he could not have been in jeopardy. In her brief, the lawyer pointed out that a vehicle that travels 50 ft. in 10 seconds would have an average speed of only 3.4 mph.


One judge in the appellate panel seized on this "glaring inconsistency" to conclude that Wyatt's "self-serving account" was "physically impossible." He wrote: "Nobody should mistake 3.4 miles per hour for 50. If the time period is cut to five seconds, the average speed only increases to 6.8 miles per hour. That is hard to mistake for 50 miles per hour, as well."


If Wyatt was inside a vehicle that, in reality, "might have been slowly rolling forward," the judge wrote, "a reasonable jury might conclude" that his shooting the driver dead was "unreasonable." He voted in favor of kicking the case back to the district level for trial.


The majority of the panel, however, upheld the summary judgment. Given the circumstances, the majority ruled, the use of force by Wyatt and his partner was "not excessive or disproportionate to the quickly escalating situation." As a captive inside an accelerating car with a resistant subject at the wheel, the officer was clearly in jeopardy, and the "absolute certainty of harm need not precede an act of self-protection."


As to the "inconsistency" of Wyatt's recollections of time and distance, these should be regarded merely as "rough estimates," the prevailing justices said. Revealing a fundamental understanding of the effect of extreme stress on memory, the court noted: "It would be surprising if an officer could recount precise quantitative details about an incident which took mere seconds" to occur. "A minor inconsistency in officer testimony does not alone create a dispute of material fact....


"The most that a rational trier of fact could that Wyatt is bad at estimating--hardly a reason to send this case to trial."


The court's decision, issued in 2013, can be accessed in full without charge by clicking here.


[Our thanks to attorney John Hoag, former faculty member for the Force Science certification course, for bringing this case to our attention.]




III. Our readers write on active shooter mindset & ER assessments


Reader responses to articles in Force Science News #248, transmitted 1/29/14, include the following, edited in some cases for brevity or clarity.


On theories about the psychology of active killers, presented in a paper by Lt. Daniel Modell, a firearms and tactics training coordinator with NYPD and a graduate of the Force Science certification course:


Expecting surrender may be "reckless"

From a common sense standpoint of an officer with 25 years of street and tactical experience, I believe that the conclusions drawn by Modell are assumptions that may lead police and civilians alike to be lulled into a false sense of security.


He and [mass-murder researcher] Ron Borsch suggest that these killers will surrender or commit suicide the minute they sense resistance or that the police arrive on scene. This has not always been the case, nor do I suspect it will be in future events.


Swift, aggressive action by civilians or a solo officer can, and has been, an effective solution. But when it is presented in such a way as to suggest a conclusive outcome, based on a predetermined response, it is reckless.


Civilian and solo officer response should be a last resort, not necessarily a standard operating procedure. Officers should continue to train in team tactics. These tactics can carry over to a single-officer response, as well. Officers should also train in a modular concept by adding officers as they progress through the threat area. When you have a multi-officer response with officers who have not trained in team tactics, their actions often add to the chaos.


Daniel Danaher

Executive Board Member

Tactical Encounters, Inc.


"Great truth" about active shooters

I believe there is great truth to Lt. Modell's views on the mind of the mass murderer/active shooter.


Chief Jeff Chudwin (ret.)

Pres., Illinois Tactical Officers Assn.


Request granted

I am writing to request use of your article on active killers when I teach active shooter and MACTAC (Multi-Assault Counter-Terrorism Action Capabilities) rapid deployment. I believe this article will help my students better understand the mindset of mass killers.


K-9 Ofcr. Larry Drake

Brookville (PA) PD


On the paper by Dr. Jared Strote, urging ER physicians to be more vigilant in following up on complaints by injured suspects who allege that they are victims of police excessive force:


ER docs not equipped to draw conclusions

Doctors in the ER don't know the circumstances resulting in injuries and shouldn't do their own investigation based only on a suspect's injuries and complaints. It's simple: If you want to be the plaintiff's expert in court, just say so. Don't try to look impartial as Dr. Strote is apparently doing.


Det. Dean Vosler (Ret.)

Bay City (MI) PD


© 2017 Force Science Institute Ltd.