Force Science News #53:

Ask The Experts: Answers to Readers’ Questions + Why Cops Aren’t Always

Wrong in “Suspicious” Shootings

In this issue:


I. Ask the experts: Answers to readers’ questions


II. Why cops aren’t always wrong in “suspicious” shootings


III. Force Science Seminar coming up fast! Register now!





Recently S/Sgt. Robert Jenks of the Jackson (MI) PD submitted this inquiry to Force Science News: Should an officer who has been involved in a shooting be shown an in-car video of the confrontation? What effect might this have psychologically?



Also Lt. Chip Dull of the Sacramento County (CA) SD asked us about action/reaction times in “likely scenarios we would face out on the street.” Specifically: Is there reliable research on how long it takes a suspect to retrieve and fire a gun from underneath clothing? How about an offender drawing from his waistband when he’s facing away from you, then spinning around and shooting or reaching around and firing as he runs away?


We put these questions to experts associated with the Force Science Research Center at Minnesota State University-Mankato. Here are their responses:


Regarding the advisability of sharing videotape of a shooting with the officer(s) involved, “the best gauge is to ask each individual officer if he or she wants to see the tape and when,” says Dr. Alexis Artwohl, a police psychologist who serves on FSRC’s National Advisory Board.


In her experience, “most officers prefer to see the tape and could benefit from it” in terms of psychological adjustment and memory enhancement. “Memory gaps and distortions are a normal part of any sudden, high-stress event, and most individuals involved have a strong desire to find out what really happened.”


Ideally, Artwohl believes officers should have a chance to review videotape and other relevant physical evidence “before giving their IA and criminal-investigation statements.” Viewing such evidence “will often help officers give a more accurate statement of what happened. In fact, all witnesses could benefit from any evidence or other cues that help trigger their memories and fill in gaps.”


Dr. Bill Lewinski, FSRC’s executive director, agrees but points out that some departments may resist sharing evidence with involved officers. Indeed, he has been involved as an expert witness in several cases in which officers were denied an opportunity to see video of their incidents and then were charged criminally when their statements included inconsistencies with the objective record.


“It depends on an agency’s investigative philosophy,” he explains. “Does the department view the officer as a possible ‘perpetrator’ of a violent act and if so are investigators looking for ways to catch him in discrepancies that could suggest lying and wrongdoing on his part? Or do they view him as a conscientious professional caught in circumstances that forced him to use deadly force as he is trained to do, and if so is their aim to establish as fair, comprehensive and impartial a picture as possible of what actually took place?


“As human beings, we are not cameras that record everything that occurs in our presence. We see and select information, and after a high-intensity event like a shooting it is normal to have memory gaps and distortions. These reflect the narrowed focus and selective attention that inevitably occur during an encounter.


“Officers need to know what the object record shows so they can put their memories into a reasonable context and report on the occurrence accurately. This does not mean they want to lie or twist the facts.


“For example, if an officer fires because he believes a suspect is threatening him with a gun and it turns out that there was no gun, seeing a video of the confrontation may help him understand why he had the impression that he did. He can then present more detail in his statement to explain his perception and give the most accurate report possible.


“Showing an involved officer a video of an incident can have the same benefit as a walk-through review before he gives a formal statement. It’s one more device for ‘mining’ an officer’s memory for maximum recall.”


Artwohl includes this reminder in her response to S/Sgt. Jenks: While “most officers who are treated decently do well after a shooting, it is still important that they have access to a therapist they like and trust” as part of debriefing the experience. Preferably a session with the therapist should take place “within 24-72 hours after the event and before the officers give any statements. They should be encouraged to see the therapist again if at any point they have issues or further questions.


“The agency should pay for these sessions, but it is essential that it be understood by all parties that the officer, not the department, is the therapist’s client. The therapist needs to have privileged confidentiality and should provide no information to the department. Nor should these sessions have anything to do with a fitness-for-duty evaluation.”


As to Dull’s questions about action/reaction times, Lewinski points out that documenting such human performance variables has historically been a core component of FSRC’s research.


Currently, FSRC researchers “are testing the motion time of drawing a gun from underneath clothing,” he reveals. Previously, FSRC studies have shown that an “average” suspect with his hand on a firearm and the weapon clear of any obstruction or clothing can draw and fire from a waistband or pocket in .25 seconds. This compares with the average officer being able to draw from a Level II holster and complete an aimed/pointed shot with arm extended in about 1.75 seconds.


“If the suspect’s weapon is obstructed by clothing, the method of clearing the obstruction will impact on the time to pull the weapon,” Lewinski says. In studies directed by firearms expert Ron Avery, a member of FSRC’s Technical Advisory Board, “we are currently testing subjects pulling guns from concealment or a covering garment to fire with some element of aiming.”


Preliminary findings indicate it is not unusual to get 3 rounds fired under these circumstances in 1.25 seconds, with good hits on target (head or center mass) at less than 15 feet, Lewinski reports. “Some slower subjects are taking more than 1.5 seconds.”


Interestingly, this study so far is also finding that the more inexperienced a subject is with a firearm, “the greater the likelihood that they will attempt a shot to the head at close distances.”


In answer to Dull’s question about spinning and shooting or running away and pointing, “the average time to do this and get a shot in the general direction of the target is a quarter-second, with the fastest being 9/100ths of a second,” Lewinski says. “This does not involve an aimed shot.


“If you do the math, we have confirmed the obvious: Action beats reaction almost every time in almost any combination you want to put together. That’s why good tactics and use of cover are key elements in surviving a gunfight.”




A strong message about deadly force encounters that critics of the police, as well as investigators and prosecutors, need to hear is sent in a feature article that appeared this summer ['06] in “The Scene,” the journal of the Assn. for Crime Scene Reconstruction.


The article, authored by Drs. Jeffrey Bumgarner, Bill Lewinski, and Bill Hudson of the Force Science Research Center and Minnesota State University-Mankato, reports details of 4 classic research experiments concerning reaction time conducted under the auspices of the FSRC with 102 officers of the Tempe (AZ) PD.


These ground-breaking studies have been essential in documenting that an officer’s defensive reaction is almost invariably slower than a suspect’s life-threatening action, that a suspect presenting a face-to-face threat can legitimately end up shot in the back because of this reactionary lag, and that an officer may involuntarily continue to shoot after a threat has ended because the decision to stop takes time for his brain and body to process.


The science behind these conclusions is carefully and clearly explained in the article. And this information is important to understand, the authors argue, because most academics, other civilian critics of police, and even many investigators and prosecutors tend to believe that every “suspicious” law enforcement shooting results from an officer’s malevolent intent.


“There is an apparent reflex to find the police at fault in almost any circumstance,” the authors observe. Critics commonly “presume improperness and excessiveness unless the evidence clearly demonstrates otherwise.


“Consequently, when the physical evidence at first glance appears to contradict the account given by the ‘offending’ police officer, there is almost never an extension of benefit of the doubt to such officers. Nor is there an assumption that a rational explanation which supports the officer’s account might exist and is awaiting discovery.” Instead, violence by police is regarded as “an avoidable tragedy that can be significantly reduced if police organizations and individual officers would get their acts together.”


In fact, “many incidents involving the apparent misuse of force by police officers can be explained by the realities of human psychological and physiological limitations. Police officers cannot be expected to defy biological and physical laws as they perform their duties. To require…flawless reaction of police officers in the field is to ask the impossible. And to send officers to prison when they fail to do the impossible is a most grievous injustice.


“Only through deference to scientific research,” like that reported from the Tempe studies, “may we begin to understand how at least some deadly force encounters play out….”


The article is well worth reading and passing along to others who need to understand its content or who may benefit from it.


It’s called “An Examination of Police Officer Mental Chronometry” (chronometry refers to how quickly the human mind and body can react to stimuli). The subtitle (“I Swear…I Don’t Know How I Shot Him in the Back”) and the article itself are much less academic. The report appears in the July 2006 issue of The Scene and can be accessed at:




Less than 3 weeks remain before the presentation in Santa Clara, CA, of “The Force Science Seminar: Winning Extreme Encounters from Street to Court.”


Mailed-in registrations must be received by Sept. 22. After that, reservations must be made by phone to save you a place for the program, which will be given Sept. 27 by Dr. Bill Lewinski, executive director of the Force Science Research Center at Minnesota State University-Mankato.


Running from 8:30 a.m. to 5 p.m., the seminar will cover the latest ground-breaking findings from FSRC about deadly force confrontations–unique information you need to know to survive, investigate or defend controversial law enforcement shootings.


Lewinski will take the mystery out of a broad spectrum of little-understood issues, including how suspects often end up shot in the back, why officers may unavoidably “overkill” their attackers and how memories of high-intensity events can most effectively be probed in fair, neutral and comprehensive investigations.


Approval of the course for training credit is pending from California POST.


To register by mail before Sept. 22, please send check for $195 per person payable to the Santa Clara Police Dept. to:

Sgt. Stacy MacFarlane, Training Mgr.

Santa Clara PD

601 El Camino Real

Santa Clara, CA 95050


For information or to make reservations after Sept. 22, contact: Reba Warren at 408-615-4861 between 7:30 a.m.-4:30 p.m. Pacific time, Monday through Friday. You can pay at the door with cash or check, but YOU NEED TO MAKE AN ADVANCE RESERVATION before the day of the program.


The seminar will be presented at the Intel Corp. Auditorium, 3600 Juliette Ln., Santa Clara, CA (convenient to the San Francisco and San Jose international airports). Check-in will begin at 7:45 a.m.


For more details on program content, intended audience and lodging, see the Special Notice from FSRC, transmitted 8/19/06. Go to:



(c) 2006: Force Science Research Center, Reprints

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Force Science Research Center, a non-profit organization based at Minnesota

State University, Mankato.



Written by Force Science Institute

September 8th, 2006 at 5:21 pm

© 2017 Force Science Institute Ltd.