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“I saw it with my own eyes”

by Donald Prothero, Jun 13 2012

Humans are storytelling animals, and they are easily persuaded by the testimony of other individuals. The telemarketers and advertisers all know that if they get a popular celebrity to endorse their product, it will sell well, even if there are no careful scientific studies or FDA approvals to back up their claims. The endorsement of your next-door neighbor may be good enough to make simple decisions, but in science, anecdotal evidence counts for very little. Yet as Daniel Loxton and I found out during our research for our new book on cryptozoology due out soon, nearly all evidence of Bigfoot, Nessie, Yeti, and other cryptids is no more than anecdotal, “eyewitness” accounts. As Frank Sulloway put it, “Anecdotes do not make a science. Ten anecdotes are no better than one, and a hundred anecdotes are no better than ten.”

Most scientific studies require dozens to hundreds of experiments or cases, and detailed statistical analysis, before we can accept the conclusion that event A probably caused event B. In the case of medicine and drug testing, there is typically a “control” group that doesn’t receive a given treatment, or receives a placebo instead, so that we can rule out the possible effects of the power of suggestion, and also rule out random effects. Only after such rigorous testing which can rule out the biases of the subjects and the observers, random noise, and all other uncontrolled variables, can scientists make the statement that event A probably caused event B. Even then, scientists do not speak in finalistic terms of “cause and effect” but only in probabilistic terms that “event A has a 95% probability to have caused event B.”

The same goes for eyewitness testimony, which may have some value in a court of law, but is regarded as highly suspect in most scientific studies. Thousands of studies have shown that eyewitnesses are easily fooled by distractions such as a weapon, or confused by stress, or otherwise misled into confidently “remembering” things that did not happen. This is vividly demonstrated by a startling video where the viewer is told to count the number of times players dressed in white pass the basketball. If you do it and focus on the counting, you will completely miss a man in a gorilla suit who walks right through the shot, because your attention is focused elsewhere.

As Levin and Kramer put it, “Eyewitness testimony is, at best, evidence of what the witness believes to have occurred. It may or may not tell what actually happened. The familiar problems of perception, of gauging time, speed, height, weight, of accurate identification of persons accused of crime all contribute to making honest testimony something less than completely credible.”  Consequently, court systems around the world are undergoing reform as DNA evidence has shown case after case of eyewitness testimony that resulted in a wrongful conviction. One famous study involved a young woman who conclusively identified the face of her rapist and sent him to prison, only to find out later when his DNA was tested that he was not the culprit. She had seen his face on television and subconsciously associated his face with her (unseen) rapist’s face. As psychologist Elizabeth Loftus has shown, eyewitness accounts of events and their memory of them are notoriously unreliable. In her 1980 book, Memory: Surprising New Insights into How We Remember and Why We Forget, Loftus writes: “Memory is imperfect. This is because we often do not see things accurately in the first place. But even if we take in a reasonably accurate picture of some experience, it does not necessarily stay perfectly intact in memory. Another force is at work. The memory traces can actually undergo distortion. With the passage of time, with proper motivation, with the introduction of special kinds of interfering facts, the memory traces seem sometimes to change or become transformed. These distortions can be quite frightening, for they can cause us to have memories of things that never happened. Even in the most intelligent among us is memory thus malleable.”

Radford and Nickell recount several examples that make this point vividly. In 2004, one Dennis Plucknett and his 14-year-old son Alex were out hunting in north Florida. Alex was in a ditch some 225 yards away from his father when someone yelled “Hog!” Dennis grabbed his gun, pointed it at a distant moving object that looked like a hog to him and fired. Instead, he killed his son with a single shot to the head. Alex had been wearing a black toboggan cap, not a hog costume or anything else that would have made him look remotely hog-like. Yet at that distance, and with the suggestion that there was a wild hog nearby, his father mistook a toboggan cap for a wild boar, and a tragic result occurred. In fact, hunting accident stories like these are common, since many hunters shoot first and ask questions later, often confused by distant objects that are moving and by the suggestibility of their own imaginations to “see” what they are looking for, and not what’s really there.

Or take, for example, the Washington, D.C., sniper panic of 2002. Early eyewitness descriptions told authorities to look for a white or light-colored box truck or van, with a roof rack. Police wasted weeks of time and caused huge traffic jams stopping every vehicle that remotely matched the description. Finally, the suspects, John Lee Malvo and John Allen Muhammad, were caught— and the “white van” was actually a dark blue 1990 Chevrolet Caprice. D.C. Police Chief Charles H. Ramsey said, “We were looking for a white van with white people, and we ended up with a blue car with black people.” All that energy and time was wasted because eyewitness accounts were wrong. The Washington Post reported that the suspects’ Caprice had actually been stopped ten times during the period of the panic because it was near the site of one of the attacks, but each time it was released because it didn’t match the eyewitness descriptions.

Many of these “memories” of strange experiences or eyewitness accounts of bizarre beasts can be attributed to sleep-deprivation, dreams and hallucinations. In his book, Why People Believe Weird Things, Michael Shermer describes how he once had an experience of being abducted by aliens. At the time, he was undergoing the stress of an ultra-marathon cross-country bicycle race, and his mind hallucinated the entire experience. As Shermer showed, most famous accounts of aliens abductions and out-of-body experiences can clearly be attributed to dreams or hallucinations caused by stress. For most “eyewitness” accounts of bizarre monsters, there is overwhelming evidence that individuals can hallucinate or imagine things that aren’t really there, or be fooled by a stressful panicked glimpse of something real (such as a bear instead of Bigfoot), and then their memory and imagination fills out the details later.

This is one of the central issues one encounters when you examine the claims of cryptozoology, as Daniel Loxton and I did in our upcoming book. Nearly every cryptid, from Bigfoot to Nessie to the Yeti, is based largely on the often contradictory and changing accounts of eyewitnesses, with no hard physical evidence of any of them that has held up to scrutiny. Cryptozoologists and Bigfoot fans place a lot of faith in what they saw or heard, or what other people report, without realizing how easily their perceptions can be fooled. None realize how fallible human perception is, and why scientists view it as the worst possible line of evidence.

What is the proper scientific approach to such evidence? As we have seen, most scientists discount it outright unless there is strong physical evidence to support it. Even the most reliable eyewitness account does not meet the standard of “extraordinary evidence” that we would need to substantiate an “extraordinary claim.”

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37 Responses to ““I saw it with my own eyes””

  1. Carl says:

    The same goes for eyewitness testimony, which may have some value in a court of law, but is regarded as highly suspect in most scientific studies.

    Actually trial lawyers and judges are well aware that eyewitness testimony is terribly unreliable. Unfortunately (and as you say) it’s compelling for jurors even if it’s not very useful in determining the truth.

    • Daniel says:

      Very rarely is anyone ever convicted on eyewitness testimony alone, or at least in the “I saw Bigfoot” sense. There’s always a dead body there, the person spotted doesn’t have an alibi, etc.

      One way to think about it, is if someone actually produced a Bigfoot specimen, or presented the aliens and their flying saucer for all the world to see, their testimony of what they saw leading up to those events would be more credible than what you see on the History Channel.

      Not to say that faulty eyewitness testimony doesn’t result in wrongful convictions, just that it’s more reliable in a court of law than in the tales of a cryptozoologist.

      • tmac57 says:

        Not to say that faulty eyewitness testimony doesn’t result in wrongful convictions, just that it’s more reliable in a court of law than in the tales of a cryptozoologist.

        What make it more reliable in a court of law?

      • Daniel says:

        Guess I was a little imprecise, but perhaps a better way to put it is that there’s more of a gatekeeping function in presenting eyewitness testimony in court than a Bigfoot. For example, you probably couldn’t even get a search warrant to search John Smith’s house if some guy walked into a police station and said, I saw John Smith shoot Jimmy Hoffa. That’s basically what every single Big Foot or UFO sighting amounts to.

        I just get a bit of a rise by equating admittedly flawed aspects of a pretty good criminal justice system with the evidentary standards of a cryptozoologist or ufologist.

      • tmac57 says:

        I generally agree with your last point,however,having lived my entire life in Dallas County,I am increasingly dubious about how “pretty good” the criminal justice system is:

        http://reason.com/archives/2010/02/08/how-many-more-are-innocent

        Whatever the percentage, DNA testing has exposed some gaping flaws in the system, calling into question traditional assumptions on the value of eyewitness testimony, forensic evidence, confessions, and the appeals process. (In several cases in which a defendant was later exonerated by DNA testing, appeals courts not only upheld convictions, but noted the “overwhelming evidence” of the defendants’ guilt.) …
        Put another way, if we now know because of DNA testing that misconduct by police and prosecutors produced a wrongful conviction in a high-profile murder case, it’s probably safe to assume that the same problems led to the wrongful conviction of a number of routine drug suspects over the years, too. The difference is that there’s no test to clear those people’s names.

        You may feel sanguine about the criminal justice system now,but take my advice,just hope that you never get caught up in it,even if you are innocent.

      • Daniel says:

        I guess I would say that the US criminal justice system, and its reasonable equivalents in most of the developed world so far as I can tell, is the worst criminal justice system except for all other. (Yes, it’s taken from the Churchill quote on democracy).

        I’m a civil litigator by trade, and believe me, I know the flaws of the system. Being a smallish type business and getting caught up in frivolous civil litigation in a US court can be devastating.

        I would add that if the criminal justice system devoted itself to solving real crimes, perhaps you’d see fewer wrongful convictions. But that’s a different issue than the merits of permitting juries to rely on eyewitness testimony.

  2. Max says:

    A hundred anecdotes are better than one. If 99 out of a hundred witnesses identify the same suspect, that’s a heck of a lot more reliable than one witness.
    Also, not all witnesses are equal. Those who actually saw the event as it happened are more useful than those who just saw the aftermath and assumed what might have happened.

    On 9/11, there were some witnesses who described a missile hitting the Pentagon, but there were others who saw not only an airplane, but an American Airlines logo on it. Now, I can imagine how one can mistake a fast low-flying airplane for a missile, but I can’t imagine how one can mistake a missile for an American Airlines airplane.

    • Donald Prothero says:

      But you missed the point: most of the “eyewitnesses” of Bigfoot and other cryptids are highly inconsistent, and give different accounts of what they saw, except when there is some cultural trend and they are all copycatting the same media account. And most are viewing cryptids under less than ideal conditions, not watching them calmly for many minutes at a time. As post 4 below points out, these would be discounted by any jury following the instructions given in that post….

      • Max says:

        Even if the accounts are inconsistent, it’s better to have a hundred of them than one to see how inconsistent they are.

  3. Max says:

    Local hunters helped scientists discover a snub-nosed monkey, advising them to survey during the rainy season and listen for the sneezing monkeys.
    http://news.nationalgeographic.com/news/2010/10/101027-snub-nosed-monkey-sneezes-new-species-science-discovered-eaten/

    • Donald Prothero says:

      And this is relevant…. how? Local hunters have many generations of experience with real animals, not just brief glimpses typical of most the “eyewitnesses” of cryptids

  4. The Midwesterner says:

    This is the jury instruction regarding eyewitness testimony from my state. As you can see, the courts are somewhat skeptical as well:

    Identification Testimony—Cautionary Instruction

    Testimony has been introduced tending to identify the defendant as the person observed at the time of the alleged offense. You should carefully evaluate this testimony. In doing so, you should consider such factors as the opportunity of the witness to see the person at the time of the alleged offense, the length of time the person was in the witness’s view, the circumstances of that view, including light conditions and the distance involved, the stress the witness was under at the time, and the lapse of time between the alleged offense and the identification. (If the witness has seen and identified the person before trial and after the alleged offense, you should also consider the circumstances of that earlier identification, and you should consider whether in this trial the witness’s memory is affected by that earlier identification.)

  5. Chris Howard says:

    Once again anecdotal evidence can be a good place to start, as long as it leads to a testable hypothesis, but it’s usually not a good foundation for a solid theory.

    If one person sees flashing lights in the sky is he less, or better able at determining wether, or not it’s an alien spacecraft, or just a plane than say one hundred people who saw the same lights? The only thing that one can determine from that example is a person, or persons claim to have seen lights in the sky. That can’t tell us if those lights are alien spacecraft, planes, gasses, fairies, gods, fireworks, or if the lights were even there to begin with. The lights could have been a hoax, or mass hallucinations.

    In other words wethere one, or one hundred people report a thing, until it can be tested, and/or physically verified via solid evidence, no sound conclusions can be made as to what a thing is. Anecdotal evidence is dependent upon supposition, and inference which makes it too unreliable to stand on its own.

    This doesn’t even address cognitive biases, thinking errors or any other myriad things which can effect, not only sensation, but perception as well.

  6. Loren Petrich says:

    Any opinion of this paper?

    Predicting the distribution of Sasquatch in western North America: anything goes with ecological niche modelling – Lozier – 2009 – Journal of Biogeography – Wiley Online Library – http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2699.2009.02152.x/full

    Its authors propose that sightings of that cryptid are really sightings of black bears. Sasquatch sightings most often occur where black bears prefer to live, and Sasquatch reportedly looks much like a black bear.

    I’ve seen a similar identification proposed for the Tibetan Yeti: the Himalayan brown bear or red bear.

    • Chris Howard says:

      Sounds like a perfectly reasonable explination- Ockham’s Razor, and all that.

      • Donald Prothero says:

        I believe Daniel saw and cited that paper in his Bigfoot chapter, so we DID account for it. I know that my Yeti chapter shows the strong evidence that most “sightings” are the Himalayan brown bear…

      • Loren Petrich says:

        Sorry if I seemed condescending, but I remember mentioning Lozier’s paper in Wikipedia’s article on Bigfoot and someone editing it out again. So it’s nice to see some appreciation of that work.

  7. Max says:

    Why is there a chimp on the book cover? Or is it Bigfoot?

  8. MadScientist says:

    No one seems interested in my anecdotal proof of the non-existence of the Yeti: I never saw one!

  9. Trimegistus says:

    Since I frequently gripe about Mr. Prothero’s forays into politics, it’s only right that I say how much I enjoyed this post. Good job!

  10. d brown says:

    I think it was in the very late 50’s I read about FBI training. They ran two people in and out of a class and had the class describe what happened. None of them were ever close to the truth. The only people who use eyewitness testimony only are people who want to lock up someone, any one. There is no way that many people were and are locked because their lawyer did not go and look and see there was no way for eyewitness to see anything of what happened. A famous climber tracked what were know to be Yeti prints in the snow to the shade. Where they turned into un-melted tracks of much smaller hopping animal.

    • Old Rockin' Dave says:

      I recall reading about a similar demonstration in a class for prospective British intelligence agents. Without any warning a man ran into the room, fired blanks at the instructor (who fell to the floor) and ran out. The instructor obligingly fell to the floor and after the shooter left got up and asked the students to write up what they saw. The accounts were, as d brown says, wildly varying. They couldn’t agree on what the shooter wore or said, how many shots were fired, what kind of pistol was used or anything else remotely useful. Some would even identify the shooter as female.
      “Are you positive that’s the person you saw?” is probably going to go the way of asking a rape victim what she was wearing.

      • Max says:

        What if you average the quantitative stuff like the number of shots everyone heard, and take the mode of the qualitative stuff like the gun type?

      • tmac57 says:

        15 people remember the gunman as having worn a yellow jacket,and 15 remember a blue jacket.Clearly the gunman was wearing a green jacket.

      • Max says:

        Or yellow on one side, blue on the other. Remember the math joke about the sheep that’s black on at least one side.

      • Max says:

        If 15 people saw a red light, and 15 saw a green light at the same time, then it could be that the light was yellow (red+green).

    • SteveN says:

      I actually tried this stunt–having two strangers suddenly come into the class, with one firing a capgun at the other–and had a large group of 100+ freshmen write down exactly what they saw. Very few got the correct number of capgun shots fired, and no one correctly reported what I had one of my confederates yell, “Sic semper tyrannus!” This is what JW Booth said after he shot Lincoln; people back in 1865 were perhaps more primed to hear and understand Latin. But today’s freshmen can hear it–and yet not understand or remember it.

      • Peter Groves says:

        “Sic semper tyrannus!” would be a self-accusation (“Thus always a tyrant [behaves]“); what Booth cried was “Sic semper tyrannis!” (“Thus always to tyrants”).

  11. WScott says:

    The scientist is correct that “the plural of anecdote is not data.” However, to most people a handful of anecdotes are far more convincing than reams of peer-reviewed data, and I suspect it always will be. So the question is how can science educators and others who care about reality use anecdotes to better illustrate and explain their data to the general public?

    Love the Pulp-style book cover, BTW!

  12. SteveN says:

    Nice piece! Reading Loftus and Schachter has, for me, really improved my scientific observation skills, b/c I now have an appreciation of just _how bloody incorrect_ seemingly simple observations can be. Especially my own observations.

  13. Scott the Aussie (in Devon!) says:

    As soon as its out I’ll order your book Don. Looks like an excellent read on one of my favourite subjects. BTW my presence was not entirely welcome at the Nessie Exhibition at Drumnadrochit a few years ago…too skeptical you see….. :-)

  14. Brian says:

    No Kindle edition?? Tell your publisher to get with it! :(