Perception, Memory, and Justice

24 November 2015

In the criminal justice system, eyewitness testimony can make or break a case. Yet our eyes can deceive us and memory can be a fickle friend. So how much can we really trust eyewitness testimony?

Psychological research reveals a lot of deeply troubling facts about human perception and memory that should make us very skeptical of eyewitness testimony. Of course, we don’t need science to tell us that if we witness something from too far away, or if it’s too dark, or if we’re intoxicated, then our testimony is not going to be very reliable. That just seems like common sense. But common sense may also lead us astray when it comes to the reliability of eyewitness testimony, and that is what a lot of the research on this topic is telling us.

Imagine the following scenario. You’re waiting in line at the bank when armed robbers enter and make everyone lie on the floor while the tellers empty their cash drawers. A tense, dramatic event like this is sure to stick in your memory, right? After all, it’s not everyday you witness a bank robbery. Perhaps while it’s happening, you’ll make a special effort to remember details, as that could prove important if you’re ever called to testify. If the event is particularly stressful, later it might even replay itself over and over in your head, when you’re desperately trying not to think about it.

You get the picture. So, the question I have for you is this: How good do you think you’d be at identifying one of the perpetrators later on in a line-up? We’ll imagine for the sake of argument that none of them was wearing a mask during the robbery. The event took place in a well lit bank in the middle of the day, and let’s assume you weren't drunk or high, and if you have bad eyesight, you were wearing your glasses or contacts at the time.

I’m guessing many of you think you’d do a pretty good job and would be fairly confident about later identifying a suspect in a line-up. But there are some other factors you may not have considered. For example, how close would you have to be to one of the perpetrators to be able to identity him later? And what effect does the angle at which you observe the perpetrators have on this ability? Recall, you’re lying on the floor during most of the robbery. So, how good would you be at identifying a suspect in a line-up (i.e. looking at him straight ahead) when you only saw him from a weird angle on the floor? And how much time would you need to observe his face in order to recognize him again later? Even if you knew how long the average person needs (unlikely, unless you study this stuff), how good are you at gauging time, especially during a high-stress event, like a bank robbery, when (your experience of) time might slow significantly? How does stress affect your ability to remember important details? Finally, if the robbery was carried out using guns or other weapons, how would this affect your ability to identify a suspect later?

Can common sense provide answers to these questions? Sure, we might all make guesses, but we might also get the answers wrong. Luckily, the scientists who research the psychology of perception and memory are providing answers and many of them are quite surprising.

Take the last question I asked about your ability to identify a suspect later—what effect would a weapon used in the robbery have on your ability? It’s not obvious that it would have any effect, right? It turns out that when a weapon is used, witnesses have an unconscious tendency to focus their attention on the weapon rather than on the faces of those holding the weapons. So, if you’re looking at the gun and not the guy, how are you going to be able to identify the suspect later?

This list of questions I asked focused on some different factors that could affect your ability to perceive or pay attention to details, such that they could be recalled later. But the psychological research also shows how easily your memory can be pulled off track. The way witnesses are questioned by law enforcement can influence and change memories. For example, if you’re asked, “Did you see the gun?” rather than “Did you see a gun?” that can affect what you think you did or did not see. In the first case, which uses a definite article—“the”—that there was a gun is already suggested in the question, whereas in the second case, which uses an indefinite article—“a”—there is no such suggestion. As far as the police know, there may or may not have been a gun. And this can actually make a difference to a witnesses memory.

That’s because memory is something that is constructed from little bits and pieces. It’s not, as we might imagine, simply a replaying of events, like watching a movie. How we put together these bits and pieces can be manipulated by external forces, whether intentionally or not. But if law enforcement don’t know about the various ways memories can be influenced, they may ask the wrong questions and end up with witnesses whose memories are not a reliable indicator of what actually happened.

Can’t this all get sorted out in court? Isn’t that why we have an adversarial system? If a witness for the prosecution is unreliable, the defense can cross examine and cast doubt on the testimony.

In an ideal world, that would be the case. But lawyers are not scientists or psychologists and they might be just as ignorant of the research on perception and memory as the next guy. And besides, jurors have all sorts of unconscious cognitive biases that can be hard to overcome. Take, for example, how confident a witness is in identifying a suspect. We’ve already mentioned some of the ways in which we may not be in a position to get a good enough look to form the right kind of memories to begin with, even if we're convinced we are. And then those memories can be manipulated. You could tell jurors about all this research, but the fact is that if a witness takes the stand and is very confident about what and who they saw and what they remembered, jurors tend to believe them. Yet the research shows that there is no positive correlation between confidence and accuracy. The confidence of a witness does not indicate that they are reliable or that we should believe their testimony.

This is why we now hear so many stories about convictions based on eyewitness testimony eventually being overturned because of new DNA evidence, sometimes years or even decades after the original conviction. Did you know that about 73% of all convictions overturned through DNA evidence were originally based on eyewitness testimony? It’s quite shocking and it’s definitely not justice. Innocent people’s lives get destroyed because other people think they see something, think they remember something, but they can be very, very wrong.

So what changes do we need to make to the criminal justice system in the light of this new research on memory and perception? When fingerprint and DNA evidence were introduced, it revolutionized the justice system. Maybe it’s time for another revolution, this time based on the latest psychological research. The question is: how do we go about integrating the findings of this research, especially when it does not give us black and white answers, the way that fingerprint or DNA evidence might. 

To learn more about this fascinating research, tune into this week’s show with our guest Daniel Reisberg, psychologist and author of The Science of Perception and Memory: A Pragmatic Guide for the Justice System.

Comments (19)


DavidPerry's picture

DavidPerry

Wednesday, November 25, 2015 -- 4:00 PM

Before I was in confuse state

Before I was in confuse state whether criminals also have the rights to do but after having study and talks on it I realize that yes they do have some rights, some human rights and social rights.
The web I studied gave this information.Criminal justice and the rights, laws, etc every thing. Now its the time for the new revolution for every person. I liked the post.

Gary M Washburn's picture

Gary M Washburn

Wednesday, November 25, 2015 -- 4:00 PM

Dawn French tells a cute joke

Dawn French tells a cute joke:
A snail is mugged by a turtle. The police ask it to describe the assailant. The snail says: "I don't remember, it all happened so fast!"

MJA's picture

MJA

Wednesday, November 25, 2015 -- 4:00 PM

The only person that can

The only person that can truly tell the future is the same person that can truly tell the past, and that is no One! =

Gary M Washburn's picture

Gary M Washburn

Wednesday, November 25, 2015 -- 4:00 PM

There is a scene in the

There is a scene in the Kipling story Kim in which there is a memory exercise which demonstrates the difficulty. Does memory serve? It is not a forensic device. The jury system was originally a group selected from the village elders and interested parties, representing victim and accused, not to establish guilt, but to decide the degree of guilt and to set a remedy in the form of a payment meant to restore peace. Most witnesses are not as unreliable in their testimony as in their willingness to name the 'perpetrator', who they very well know. But the effort to make of memory a forensic tool is futile, and not a properly philosophical issue. If you have ever been to a reunion after many years it is easy to see how the senses are not the basis of recognition. What is, is intimacy. It's amazing how we share in each other's character, and how, even after decades of estrangement, can recognize ourselves in each other in a way that newer acquaintances cannot fathom. And through all the people we get to know in life it is astounding the clarity of this distinct sense in which we know ourselves through each other in the character of that person, and can remember astonishing details of what we share with them, even to the point of not repeating the same joke. This is an amazing achievement, but it is the case because memory does not serve as a forensic tool. But, nevertheless, it is that intimacy we can achieve in recognizing ourselves in each other that is the basis of the reputation of the eye witness in a court setting, going back to Anglo-Saxon law. On the other hand, the tradition of the detached observer of the modernist era is a farcical perversion of the facility we have to know and identify each other, and it combines perniciously with a tradition in which crime is the act of the stranger, the lower class or racial or colonial other, never to be recognized as 'one of us' in any case, and so never the certitude of intimate recognition and therefore relegated to 'objective' or forensic 'observation'. It is as legally unsound a judgment as it is a vapid philosophical issue.

Harold G. Neuman's picture

Harold G. Neuman

Friday, November 27, 2015 -- 4:00 PM

As you have aptly

As you have aptly demonstrated in your post, eyewitnesses are notoriously unreliable for all the aforestated reasons. Additionally, people are as they are. They are notoriously biased, whether those biases are motivated by racial animosities, cultural disparities, language differences and/or other sociological characteristics that cause one group to dislike, disdain or distrust another. The record of our criminal justice system is checkered, at best, as an examination of convictions will readily reveal. Yet another damning factor is the difficulty encountered when facing a jury "of one's peers". This tried and true tool of jurisprudence is becoming more and more problematic. How, then, do we assemble such an impartial panel when facing the same sorts of discrepancies mentioned in the third sentence of this commentary? Moreover, perhaps, how do we fairly justify a jury of peers, if they truly are such and might therefore wish to set free a guilty member of their elite? I fondly recall a quotation from Karl Jaspers: Reality is an endless fabric of meaningful and meaningless factors. Oh the web we weave when first we practice to deceive!
Warmest,
Neuman.

Gary M Washburn's picture

Gary M Washburn

Sunday, November 29, 2015 -- 4:00 PM

The obsession with

The obsession with distinctions will be the undoing of philosophy if we suppose them the avenue to the holy grail of induction. The reason distinctions are of value is because, being reductive, they help us grasp the inductive sense of the end of that reduction in bringing us to recognize that the most encompassing term of reason is the lost antecedent, not its confirmation. That is, the law of the excluded middle is not validly axiomatic. If it were, we would not be able to reason at all. If A is B and B is C, the middle term, B, can hardly be excluded from our finding A is C! And yet, in the sense of that finding, B is neither! And Wen diagrams are no help. Even a strict Sorites always leaves something out. And so, the faculty of distinguishing one thing from another can never establish the meaning of our terms, and it is the loss of that faculty, as the most rigorous term of its reductive force, that is the engine and in a real sense the originary term of that meaning. And that is the holy grail so elusive to a mind insensible to the loss of its antecedent in the very act of reasoning from it and from what is taken as axiomatic in it. This is the Modernist enigma, and the clue to the dilemma of the eyewitness.
Justice is social peace, not getting the bad guys. The obsession with identifying the guilty party is part of a system of separation, of making war on ?criminality?. That is, instead of giving the criminal the means of naturalizing himself back into the community we discern separate and stigmatize. This is part of a system of domestic colonization. It is no accident that the Norman rulers of Anglo-Saxon England tried to impose Latin legal codes and French styles of legal process, even though the laws they so framed were essentially indigenous. This was about power, not justice. Roman law was less a matter of justice than it was of precise performance of ritual, and it was the first to blunder in the process that usually lost its case. The process was one in which each side attempted to frame the case in terms of one of a set of legal mottoes, and this is why law today is so annoyingly loaded with inscrutable Latin phrases, like ?certiorari? or ?in haec verba? meant to make us all feel stupid or hopelessly naive in the presence of the initiated, and ready to swallow the result (or pay the bill!). But this obfuscation of the meaning of justice gets a little clearer if we make a sharp distinction between memory as a forensic tool, and memory as a part of what reason is.
The reason we still rely on eyewitnesses in court is the same as our reliance on them in identifying the dead. It is intimacy. It is because we value them that we are called upon to give a name to the dead. But the witness in a court today is too often called upon, not to value, but to evaluate. One recognizes a part of one's domestic life, the other establishes as outlaw to it. This is why the same intuitive reflex can have such opposite rates of reliability. Estrangement is no faculty of identification. The witness demands it must be the one, the loved one in the morgue says it can't be. The point of reliability should be obvious. But if the legal system recognized justice as social peace rather than estrangement, the difference would not be so pernicious.
I have some small experience with Alzheimer's victims. One effect of this is the eerie sense that I, too, am suffering similar symptoms. But a closer look teaches something about how memory really works. When I forget, I know this, and I have a sense of how to refresh my memory. But in no sense is that process a matter of accessing some preserved record. Memory is not a place in the mind, nor is it a fixed preserve of past events. It is a cascade of reminders, neither by association nor by some mechanics of existing 'neural pathways'. It is a process of creation. What we remember first and foremost is whereabouts, presence, a mood or impression of the character of our being there. There is no language for this feeling, though it is the most normal state of mind, perhaps so much so that we have yet to get around to examining it. Science, religion, psychology and even meditative systems let us down in this. But when the trigger is activated the cascade is so spontaneous that all of a sudden what seemed infinitely inaccessible is suddenly pulled into a complete vision and array of feeling. The Alzheimer's victim is bereft of these triggers. This is palpable to any extent of observation. Looking right at the reminder doesn't trigger the cascade of collected thought. This is why there is no locus to who we are, to what mind and reason and memory is. In a real sense it hasn't happened yet. We have to keep doing it, though it is said that if we live long enough we will all lose the faculty to do so. I do know that as I get older I get distracted from the needs of life and more lost in thought. Or is it found? For it is one of the abiding enigmas and vexations of life that we lose ourselves in distinguishing which one is which and remembering what to do next, in an endless sequence of evaluations forgotten the value of it all.

Zeneth Culture's picture

Zeneth Culture

Sunday, November 29, 2015 -- 4:00 PM

"Disability is a matter of

"Disability is a matter of perception. If you can do just one thing well, you're needed by someone." - Martina Navratilova
 
We as humans have imperfections. It is essential to always have a positive attitude and a slightly comic view to life.
https://www.zenethculture.com/life-and-your-numbers/

Harold G. Neuman's picture

Harold G. Neuman

Friday, December 4, 2015 -- 4:00 PM

Just remembered another

Just remembered another Jaspers tidbit:
Truth varies according to the origin of its content.
Wrap your minds around that one, folks. I think it must mean something like: there is no truth other than that which does not require human approval. Or perhaps more succinctly: there are three versions of the truth, 1) what I think it is, 2) what you think it is, and, 3) what it really is.
Warmest regards, Neuman.

Gary M Washburn's picture

Gary M Washburn

Friday, December 4, 2015 -- 4:00 PM

Or maybe he meant something

Or maybe he meant something like Foucault's sense of "archeology"?

MJA's picture

MJA

Saturday, December 5, 2015 -- 4:00 PM

The three versions or visions

The three versions or visions of truth, 1) is, 2) is, and 3) is.
How simple truth is.
= is

Gary M Washburn's picture

Gary M Washburn

Saturday, December 5, 2015 -- 4:00 PM

The ontological fallacy is

The ontological fallacy is what it is. What it is!

Gary M Washburn's picture

Gary M Washburn

Sunday, December 6, 2015 -- 4:00 PM

The rules of evidence are

The rules of evidence are dismissive of a witness's self-examination. The witness is not permitted to question the intention of the questions directed at him or her, nor to adress the jury or judge directly, or to mitigate or qualify responses. Juries, similarly, are expected to be passive observers. In England, juries can interrupt testimony to ask questions, and the prosecution is not a government agent in close association with the police and court, they are contracted, in the same way the public defender is contracted here. An elected prosecutor has every incentive to cheat, and many, if not most, do. It is a perversion of rational investigation. Reasons can always be found to support a predetermined conclusion, especially if contrary evidence is ignored or excluded. The defense may fill in the other side, but this sets up a decision between sides that is toxic to truth, and to justice. We don't chose sides based on the facts if we are not responsible for exploring all evidence contrary to our own prejudices. Basic themes of reason do indeed take on different implications depending on the origin of their terms. What Jaspers was getting at was very likely, and much more fully developed, by Foucault, as in works like The History of Sexuality, and Birth of the Clinic. Are we trapped in the historical terms of our presumed powers of reason, as the jury is trapped in the panel, sworn to silently observe as a travesty of 'investigation' takes place before them, and kept in ignorance of the full scale of their rights, and of the complete process of evidentiary rules? It may be as serious an issue as the accuracy of the perception and memory of the witness that the prosecutor has probably coached him or her in how to deflect the doubts provoked by the defense. Prosecutorial crime is often more eggregious than the indictment. This is especially tragic since what most poor communities need, as much as a good school system and a fairer shot at the opportunity of a good life, is dilligent, but fair and respectful, policing. There is a lot more to perception and memory than systems of observation and retreival. Fallibility is indispensable to a fair review of the facts, let alone the experience of them. To err is human, to lie (and get away with it) is divine!
 
Michael,
I hope you take the time to read the Euthydemus, you may find yourself eeriely reflected in it.

MJA's picture

MJA

Sunday, December 6, 2015 -- 4:00 PM

I see my reflection in

I see my reflection in everything, equally. =
Reflection
Seeing your reflection on a calm river can reveal a true picture of Oneself. Ripples like complexities and disorders that are normal to life can distort who One really is. During rough times, life can make the truth impossible to see. Calming self externally and internally, One?s true self becomes clear.
Find your reflection, calm yourself, and be true.
And beyond reflection?..
=

Harold G. Neuman's picture

Harold G. Neuman

Sunday, December 6, 2015 -- 4:00 PM

Another fairly learned soul

Another fairly learned soul has written what might be the definitive essay on the topic of truth. I recommend it.
Look for: ON TRUTH, by Harry Frankfurt. A small book, to be sure-but so deep in its simplicity.
Neuman.

willfree's picture

willfree

Sunday, December 6, 2015 -- 4:00 PM

Perception is colored by

Perception is colored by expectation. Memory, a questionable perception of the questionable mental trace of an earlier questionable perception, is trebly suspect. I could provide enough examples from my own life to make the reader doubt anything I say.

Gary M Washburn's picture

Gary M Washburn

Sunday, December 6, 2015 -- 4:00 PM

Fine, but does that help you

Fine, but does that help you find your keys? And even if observation and memory are put in their rightful context in a trial, the problem remains how to pursue justice in an era of sense and memory skepticism. DNA sample the world and flood our cities and towns with surveillance? In a world where everyone is watched, who watches the watchers? Too much talk of justice presumes that the purpose of a trial is not to find the guilty and to establish a regimen of reconciliation, but to identify those unworthy of social rights, and to permanently remove them. Where that mood governs the proceedings fallible perception and memory is the least of the problem.

Gary M Washburn's picture

Gary M Washburn

Monday, December 7, 2015 -- 4:00 PM

All those reflections! If

All those reflections! If flattering, I wouldn't trust them. That's why I don't look for my reflection. In fact, it is precisely the problem being discussed here that we too easily see our own reflection instead of what is really there. I suppose there is some virtue in not seeing enemies everywhere that is not our own reflection, which is the other side of the same coin. But it is only where we find only in the stranger an opportunity to be more who we ourselves are that we are ready to do justice. Where memory serves, remembrance and its motive are secreted from each other. With that secretion, tyranny begins. 
It is to foil that tyranny that memory does not serve. Used well, that fallibility is a virtue.

MJA's picture

MJA

Wednesday, December 9, 2015 -- 4:00 PM

A mental experiment: Try to

A thought experiment: Try to write down your prior day's activities from when you woke to the end of the day in complete detail, when finished, wait an hour and then repeat the exercise and write the story again. Has the story changed in any detail? And if so which is most likely, then which story is correct?
I rest my case Your Honor,

Gary M Washburn's picture

Gary M Washburn

Thursday, December 10, 2015 -- 4:00 PM

The prosecution defaults?

..., and the judge directs the jury to disregard it. The issue is not that memory is fallible. There is still something we call memory, however fallible. The question is, for what can it be relied on. Sometimes a fallible memory is the most objectively valuable evidence. For instance, where clear forensic evidence proves guilt, can a character witness exculpate?