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Cops more forgetful after chases or altercations
March 20th, 2012
02:30 PM ET

Cops more forgetful after chases or altercations

Police officers who engage in at least 60 seconds of intense physical energy while involved in a combative encounter may suffer memory loss, according to a newly published study in the journal Psychological Science.

Researchers found that officers chasing down a suspect or engaging in a physical altercation with someone can often forget details of the incident, including being unable to identify the suspect from a lineup.

The study's lead author, Dr. Lorraine Hope, University of Portsmouth, United Kingdom, said the study's findings are a "warning" to officers, police chiefs and even the court system.

"Police officers are often expected to remember in detail who said what and how many blows were received in the midst of physical struggle or shortly afterwards," said Hope. "The results of our tests indicate it may be very difficult for them to do this."

The study followed 52 police officers - 42 men and 10 women - in Winnipeg, Canada, who had been on the job about 8 years. All exercised regularly and were considered fit and healthy.

The officers were split into two groups; both groups attended a briefing and got information on three armed robberies. They viewed a six-person lineup of color pictures. The group was split into pairs where one officer rigorously assaulted a punching bag until he was visibly tired, the other did not. They were then taken to a trailer set up to represent a realistic "home" environment complete with a "target" individual who had access to multiple weapons strategically placed around the room.

Each officer went through a scenario where there was a brief but angry verbal confrontation with that person. Shortly after the scenario was over, officers were given three memory tests. They were asked to recall details of their initial briefing, the encounter - and then shown the lineup photographs.

Researchers found the group that physically exerted themselves remembered less information from the original briefing and the encounter with the target individual. In fact, more than 90% of the officers in the non-exertion group could recall at least one detail about the target. Barely a third of the officers who were involved in the physical activity remembered seeing the target person at all.

"As exhaustion takes over, cognitive resources tend to diminish." Hope said. "The ability to fully shift attention is inhibited, so even potentially relevant information might not be attended to. Ultimately, memory is determined by what we can process and attend to."

Sgt. Jason Anderson, a use of force instructor with the Winnipeg Police Service said the research will help training officers learn more about what can happen under adverse conditions.

"It will allow officers to understand that they are not 'wrong.' 'lying.' or lacking 'what it takes' because they cannot remember certain aspects of a volatile, life threatening hand-to-hand physical combat encounter," said Anderson.

The study, he said, reinforces the idea that it's OK to say, "I don't remember" or "I can't recall."

"That is simply reality," said Anderson.  "I don't care how good of shape you're in, when you reach your personal physical breaking point or extreme exhaustion, your sole focus is on remaining conscious and alive.  Your memory will be adversely and dramatically effected during a combat encounter."

All the study participants remembered seeing the angry suspect in the trailer. But the non-exerted officers provided a "significantly more detailed description" of him and made half as many errors in recall as those who were exhausted, the study said.

"These observers were also twice as likely to correctly identify the suspect from a line-up," according to the research. There was no difference in how the officers registered threat cues.

The study is the first of its kind to test eyewitness recall after physical exertion, researchers said.  Anderson believes  it will have far-reaching implications for law enforcement and court cases.

"Law enforcement can now back up our subjective beliefs and observations for the first time using science to support us,"  Anderson said.   "It is OK to say, 'No, I do not recall the color of his hat,' 'No, I can't remember what he or that bystander said,' 'No, I don't recall how many punches, knee strikes, elbows, etc., that I delivered or exactly where I delivered them."

Anderson said that ultimately, "under extreme exhaustion and attack, officers are trying to go home. They are trying to stay alive.  People need to be educated on the realities of these encounters.  This study is an extremely important tool in this education."

The Winnipeg Police Department has not made any changes based on the study results, but uses the findings when training recruits.


soundoff (36 Responses)
  1. Tinman

    It is not unusual for anyone who has been placed in an extreme stressful situation to fail to recall everything as it happened. It is the old physiological naturally ocurring human response to a fight or flight situation. When placed in such a situation the human body reacts accordingly. The blood leaves the limbs and concentrates in the core. Tunnel vision occurs to focus on the threat as does hearing. It is no wonder that often the views of an arresting officer and the person arrested remember different versions. Even a wittness to such a situation, not usually confronted with serious stress, could have the same naturally occurring reaction.

    March 20, 2012 at 15:57 | Report abuse | Reply
  2. Chuck

    Just more reason to equip officers with audio/video recorders.

    March 20, 2012 at 16:04 | Report abuse | Reply
    • jerry

      Fullerton Ca cops destroyed their recorders when they raped women in their pimp mobiles. I mean police cruisers.

      March 20, 2012 at 17:46 | Report abuse |
    • boyu

      the recordings should be wirelessly uploading information to cloud network so no one can change the information.

      March 21, 2012 at 03:30 | Report abuse |
  3. bobh

    Another excuse a cop can use to get out of a embarrassing situation.

    March 20, 2012 at 16:56 | Report abuse | Reply
  4. rika33

    Yeah – but amazing enough they all remember or don't remember the same things when its convienient

    March 20, 2012 at 17:39 | Report abuse | Reply
    • sonny

      one thing they never forget is how to abuse and torture innocent people and then lie about it.a cop can remember a lie he told 3 years ago and remember it word for word.

      March 22, 2012 at 08:33 | Report abuse |
  5. jerry

    An absent minded cop never forgets to shake down a suspect for money.

    March 20, 2012 at 17:42 | Report abuse | Reply
  6. jerry

    An absent minded corrupt cop does not forget to lie in court.

    March 20, 2012 at 17:42 | Report abuse | Reply
  7. jerry

    An absent minded cop does not to use a taser or pepper spray on an unarmed citizen.

    March 20, 2012 at 17:44 | Report abuse | Reply
  8. bobh

    What's an absent minded cop say when he wants a doughnut?

    March 20, 2012 at 19:34 | Report abuse | Reply
    • Kandi

      I don't know!

      March 20, 2012 at 19:43 | Report abuse |
  9. Larry

    Jerry, you are obviously a person who has had several 'run ins' with the police. And...I'll bet that you were never in the wrong... I have a suggestion...why don't all of the police in the country take a week's vacation? Then, when they go back to work, no reports will be taken about any of the previous week's activities. Do you think that you'll have a better week?
    Do you sleep well at night? Thank our soldiers and the police. Our society would cease to exist without either of them.

    March 20, 2012 at 19:49 | Report abuse | Reply
    • Stefan

      No, our society would cease to exist if not for the function they perform. How they perform it, and who performs it, is of course fair game for discussion.

      I've had a handful of interactions with police officers in my life. In a few, the officers were respectful and friendly, and I showed them respect. In a few the officers were much ruder than they needed to be, condescending, and bullying. I dealt with it.

      But in one situation, because I was using a port-o-potty that apparently was off limits, an officer blindsided me, physically pushed me around, and when I complained (verbally, not physically) pulled his gun on me. I am very lucky I was in a public, and very crowded, place. Because that CITIZEN might have killed me, and if I tried to stop him, I'd be in jail. You've probably never had that feeling – that someone who is no better than you is wronging you, and if you try to do anything about it, you'll be punished for it. Because if you did, you wouldn't want to give those people more leeway to harm you.

      This study I'm sure has some good practical applications. But it could also be abused by many people. Police officers are human. And unfortunately, many of them (not the majority of course) are flawed humans. When you have a hammer, all the world looks like a nail. And when your job is to fight crime, all the citizens look like criminals. It takes a special type of person to do that job well. We need legal protection from the officers who don't have the personality for it..

      March 21, 2012 at 09:24 | Report abuse |
    • Myto Senseworth

      I would sleep better if you locked up the cops and let the dope dealers go home.

      March 21, 2012 at 16:22 | Report abuse |
    • Miss Such-and-Such

      Larry:

      With no cops to worry about, I can defend myself with no consequences. Sounds great to me.

      March 22, 2012 at 16:04 | Report abuse |
    • Patsy McShelayle

      Maybe your society would cease to exist. Mine would carry on in peace. The mentality of police and soldiers is what causes the most pain and suffering on theis or any other planet. As long and people with guns think that they are keeping the peace with a weapon is shortsided. Just pecause you served time in the military or as a law enforcement professional does not give you the authorization to deny me my god given rights. I agree that as long as the "good"cops turn their heads to the crimes of their co-conspiritors it removes their standing as good.

      March 22, 2012 at 16:43 | Report abuse |
  10. Kandi

    There are no good cops. It is proven at every beating on the street. The good cops turn their heads and walk away. They are as guilty as the cops beating the unarmed guy laying on the sidewalk. Then they say "I don't remember" during the investigation.

    March 20, 2012 at 20:01 | Report abuse | Reply
    • Steve C.

      I must agree Kandi. Where are the good cops when someone innocent is being beat up on the sidewalks? You see the videos of them walking away with their tails between their legs. Cops are pigs. It is all about the pig parties they have. My brother is a cop in Tucson. I have been to their pig parties. They laugh and make fun of what they did during the week. It's shameful.

      March 20, 2012 at 21:39 | Report abuse |
  11. Larry

    I'm certain that you have direct, personal knowledge of every instance. The next time you need assistance, call Jerry. Maybe, he's the answer to all of your problems!

    March 20, 2012 at 20:21 | Report abuse | Reply
    • sonny

      thank you officer Larry for your unbiased comment i can tell by your comment that no matter what a cop does your going to stand up for them but see if that helps you out next time you get stopped for a traffic violation.just tell the cop how much you admire and respect him,i bet you still get a ticket.please don't reply i have no time for your ignorance today.

      March 22, 2012 at 08:42 | Report abuse |
  12. haha

    The amount of ignorance in the comment section here is amazing.

    Good stuff!

    March 20, 2012 at 20:23 | Report abuse | Reply
  13. And then I turned around and took his gun away....

    The way they tell war stories to each other after the chase is over shows no lapse of memory whatsoever.

    March 20, 2012 at 21:41 | Report abuse | Reply
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    March 20, 2012 at 22:27 | Report abuse | Reply
  15. jerry

    An absent minded cop wouldn't use verizon.

    March 21, 2012 at 01:45 | Report abuse | Reply
    • lepre

      an absentminded cop would use a squirrel gun jerry

      March 24, 2012 at 02:11 | Report abuse |
  16. Capt36

    Although I agree with the findings of this 'study', I see it for what it was intended to do: Exonerate the police, whenever it suits them...... The courts will always side with the police recollection, before believing any other 'non police' witness.
    I recall my first introduction to the court system, where the judge actually told me, in court, that the officer's testimony would always be believed, over mine.
    The charge was 'running a STOP sign'. The real fact was that I had stopped twice for cars in front of me, and that I had allowed the car across the intersection to take a left turn in front of me. I had actually waved him my permission, after I came to 'a complete STOP', for a third time.... The officer was located a block away, on the intersecting road, and was issuing his quota of tickets for the day….. The intersection had STOP signs for all directions, and a left turn lane for the cars opposite of me....

    March 21, 2012 at 07:43 | Report abuse | Reply
    • Stefan

      "Although I agree with the findings of this 'study', I see it for what it was intended to do: Exonerate the police, whenever it suits them......"

      That about sums it up. Fine, when people are tired their memories lapse and their mind doesn't perform. That doesn't mean you can convict someone when the police officer 'does not recall' key details. Innocent until proven guilty.

      Also, a study of 50 individuals, from the same police department, aint much of a study. They should do the same study with non-police officers, and officers from a broader area.

      March 21, 2012 at 09:36 | Report abuse |
  17. Fargo

    Not surprising. With the amount of brainpower most cops have, they are operating close to mental capacity even when standing idly on the corner. So, it boils down to either concentrating on beating some kid with your nightstick, or remembering what your victim looked like before you beat him to a bloody pulp. Often times they even forget to plant the drugs when finished.

    March 21, 2012 at 08:33 | Report abuse | Reply
  18. Survivor

    Why would cops remember any better or worse than anybody else. What I have observed first hand makes me believe that cops invent a lot of what they say in court to make it sound good I guess. I would never expect to get a fair trial in the USA if a cop was testifying.(Remeber.. if you get a ticket, you are guilty until proven innocent.) They are never there to stop crime anyway. (unless they are commiting the crime.)

    March 21, 2012 at 16:08 | Report abuse | Reply
  19. Myto Senseworth

    Have the courts appoint a scribe to accompany the cops to insure the facts are written down....and I know....I know......after the first profitable bust the scribe would be corrupted too.

    March 21, 2012 at 16:35 | Report abuse | Reply
  20. dick gosinya

    More "twinkie" defenses for cops that can't keep their emotions under control. I'm sick of the excuses given to law enforcement. Man up or quit.

    March 22, 2012 at 02:17 | Report abuse | Reply
  21. Shawn

    It's amazing how people oversimplicate things to fit their agenda. All because they are threatened by those in a position of authority.

    All you have to do is read any study or book done by Lt. Col. Dave Grossman to get a clear understanding of human behavior during confrontational situations and afterwards. The human body adapts to situations quite well, but often times the end result to your body adapting to those situations is short term memory loss, short term loss of motor skills, ect.

    It all has to do with the nervous system allocating resources to things it deems are more important to survival during a confrontation.

    March 22, 2012 at 14:11 | Report abuse | Reply
  22. Miss Such-and-Such

    So how come cops are allowed to forget, but their victims aren't? If you get accosted by a cop on the street, then the jury and judge will expect YOU to remember every irrelevant detail. Otherwise, they conclude you must be lying. But the cop, oh, that's OK, he doesn't need to remember a thing. He can just make up his own story if he wants.

    March 22, 2012 at 15:59 | Report abuse | Reply
  23. Patsy McShelayle

    The problem is that innocent people are made to suffer because an aggitated human with all the flaws and weakness of the rest of us fill out reports of what happened to pass along to people that were not there so that they can punish the person that may or may not have done anything wrong. This is great research and I hope to use it in my defense against a deputy that got the facts of our interaction wrong. I was just thinking that he was lieing for no good reason and here I am presented with a evidence that it is natural for them to make up facts to fill in the blanks. Can I get the people that did the study to bankroll my legal defense?

    March 22, 2012 at 16:29 | Report abuse | Reply
  24. Adam

    I hate when the media gets a hold of articles like this. While, yes, they are very valid with solid scientific data to back up the findings, the incompetent people of this world immediately take over and see it as excuse to bash police officers. Maybe if people didn't run and or break the law, this wouldn't even be an issue. but since it is, at least there are people who sacrifice themselves to bring non law abiding citizens to justice to keep this world in some kind of order!!

    June 19, 2012 at 14:09 | Report abuse | Reply

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