tests and demonstrations of limits of human observation

Witness Error: Tests & DemonstrativesScales of justice



tests  ·  ‘look out for cyclists’


tests  ·  ‘don't judge too quickly’


tests  ·  witness recall  ·  eyewitness id


filtered reality  ·  gestalt  ·  logo tests


Visual tests and demonstrations showing that observers and witnesses:

Test yourself and your friends. Challenge witnesses in deposition and trial. Use as demonstratives with experts. Play in openings and closings. Show jurors.

Observation & Awareness          Tests  ·  Cyclists Spots 


Witnesses can be unaware of people, objects, and events in a situation, despite being attentive to the situation. A witness's attentional focus affects what the witness observes. A witness might state that he or she did not see a person or object, despite that person or object having been present.

ComCon offers a number of visual resources to view, test witnesses' skills, and/or play during trial to help jurors experience directly that attentive witnesses may not be aware of the presence of people or objects in a situation.


Psychologists have developed a number of awareness tests demonstrating how easily people miss clearly presented information when observing a situation.

The effectiveness of these awareness tests hinges on viewers never before having seen the test. An aware viewer, on subsequent presentation, generally does not miss the information that viewers who have never before taken the test miss.

Try these awareness tests on yourself, test witnesses in depositions, or show them to a jury to demonstrate how even attentive witnesses can miss information.

Watch  Video The Card Test

Watch  Video The Count F Test

Watch  Video The Blink Test

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Watch  Video The Phone Answering Test

Watch  Video The Conversation Test

Watch  Video The Color Change Card Test

Watch  Video The Dribbling Test

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Now take the "Road Test." The first video shows you the situation. The second video shows you the answer. When the answer is revealed, ask yourself: Did you see it? and Did you see it the same way in slow motion?

Watch  Video The Road Test Situation

Watch  Video The Road Test Answer

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A public service campaign encouraging people to “look out for cyclists” ran a number of fun and interesting television spots that presented viewers with awareness tests.

Take the tests, test witnesses or show them to a jury to demonstrate that witnesses might not attend to unusual information or changes happening before their eyes.

Watch  Video Basketball

Watch  Video Chest Rotations

Watch  Video Phone Jokes

Watch  Video Who Dunnit?

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 Learn more about Awareness   

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Observation & Judgment          Tests  ·  ‘Don't Judge Too Quickly’


Witnesses make judgments about what they see as they observe other people behave, judgments that can be inaccurate and misleading when witnesses are unaware of circumstantial information or faced with circumstances in which judgment is difficult.

What a witness recounts he or she saw may be an inaccurate description of situations, objects, people and events.

ComCon offers a number of visual resources to view and play during deposition and trial to test witnesses, and to help jurors understand that well-meaning witnesses may (a) lack the ability to judge accurately or (b) lack circumstantial information and so judge incorrectly and recount inaccurately.


Psychologists have developed tests of how well people are able to make judgments of the physical qualities of what they observe. Height, length, size and color are common physical qualities witnesses report. Test yourself, challenge witnesses, and show juries.

Watch  Video Circumference vs. Height Test

Watch  Video Building Length Test

Watch  Video Line Length Test

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Watch  Video Car Size Test

Watch  Video Mug Size Test

Watch  Video Alignment Test

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Watch  Video Color Shade Test

Watch  Video Checkerboard Shadow Test

Watch  Video Dot Background Test

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Watch  Video Circle in Light Test

Watch  Video Dog Color Context Test

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Witnesses lacking circumstantial information can make judgment errors about what they believe they observed. Ameriquest produced numerous and amusing commercials with the slogan “Don't Judge Too Quickly” that demonstrate judgment errors when observers lack circumstantial information when observing other people's behavior.

Watch  Video The Girls

Watch  Video The Brownie

Watch  Video The Hospital

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Watch  Video The Parking Meter

Watch  Video The Romantic Dinner

Watch  Video The Plane Ride

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Watch  Video The School Bus

Watch  Video The Breakfast

Watch  Video The Market

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Ameriquest's ‘Don't Judge Too Quickly’ commercials struck a chord, and other companies and independent individuals produced related spots focusing on the judgment errors that occur when observers lack circumstantial information. The takeoff spots are more serious and risque. Be advised that some of these spots might be offensive to some viewers, and so are organized here from least to most risque.

Watch  Video The Implant

Watch  Video The Deodorant

Watch  Video The Bathroom

Watch  Video The Office

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 Learn more about Judgment   

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Observation & Memory       Tests  ·  Recall  ·  Eyewitness ID 


Memory does not work like a digital recorder or a computer. Memory is pliable, suggestible, associative, forgetful and fallible.

ComCon offers a number of visual resources to view and play during trial to help jurors understand that witnesses' memories may not be accurate.


Psychologists have developed a number of memory tests demonstrating how difficult it is for people to remember details accurately, and how easy it is to recall them inaccurately.

Try these memory tests on yourself, and show them to a jury, to demonstrate how even motivated witnesses can fail to recall information at all, as well as to recall information inaccurately with certainty.

Watch  Video The Flowers Test

Watch  Video The Images Test

Watch  Video The Mystery Test

Watch  Video The Words Test

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Witnesses' memories are malleable and shaped by the questions they are asked about what they observed.

The following videos demonstrate and discuss how the questions asked influence both witnesses' answers and how the answers are understood.

Watch  Video Question Phrasing: Car Accident

Watch  Video Memory Distortions: Loftus Research

Watch  Video Don't Talk To Police: Lecture Test

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 Learn more about Witness Recall   



Eyewitness identification of criminal suspects relies on memory, the very memory that is pliable, suggestible, associative, forgetful and fallible.

The Wells Crime

Dr. Gary Wells studies eyewitness memory by presenting videotaped "crimes" to "witnesses" and then asks these witnesses to identify the suspects in lineups. The first video shows one of Dr. Wells' "crimes" and its associated "lineup", and the second video reveals the actual suspect.

Take the test, or show the test to a jury, to demonstrate how even attentive witnesses can identify an innocent person.

Watch  Video Crime and Lineup Test

Watch  Video Actual Suspect

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The BBC Crime

The BBC took a group of people to lunch and made them witnesses to a murder staged live by actors. The first video shows the enacted murder, the second video shows the lineup, and the third video reveals the identity of the murderer.

Take the test, or show the test to a jury, to demonstrate the difficulty of doing a witness identification.

Watch  Video The Murder

Watch  Video The Lineup

Watch  Video The Murderer Revealed

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 Learn more about Eyewitness ID   

Observation & Perception     Filtered  ·  Gestalt  ·  Logo Tests 


Whenever people observe anything, they must process what they see. People do not process identically what they see. Two people can look at the same object and “see” opposing things. Many people can look at the same object and “see” what isn't real.

ComCon offers a number of resources to show during trial to help jurors understand that a witnesses' perceptions can differ from each other, and from reality.


People believe their own eyes. Further, people believe that what they see is determined solely by the world outside of themselves, and that anyone else looking at the same object would see fundamentally the same thing.

In reality, what people “see” is determined by who they are and what they expect to see.

Take these tests, and show them to a jury, to demonstrate that witnesses can be mistaken and need not be lying when they disagree or misperceive.

Which way is the dancer turning?

Do you see the dancer turning clockwise or counterclockwise?

Some people see the dancer turning clockwise, while others see the dancer turning counterclockwise.

With effort, by staring at the shadows, the feet, different parts of the torso or other parts of the picture, people can sometimes change the direction they see the dancer turning.

If you use a different browser you can sometimes change the direction you see the dancer turn because the dancer spins at different speeds in different browswers (e.g., she turns faster in Firefox than in Internet Explorer).

Spinning Dancer

Do you see the room as it is, or as you expect rooms to be?

Are the girls vastly different in size, or is the room of different proportions?

People see what they expect to see, rather than the world as it is. Our memories guide, and distort, what we see.

Watch  Video The Room


What object is on the table in front of the girl?

What are your observations, and what are your inferences?

People have difficulty separating what they see vs. what they think they see.

Watch  Video The Object


Who is angry and who is calm?

Are you at your computer, or 8 feet away?

The farther you are away, the more "blur" there is in what you see. With increasing blur, the emotional expressions change.

Watch  Video Angry and Calm


How do you describe the faces?

Are you disturbed by the faces?

Decoding of facial expressions works best in the orientation where faces are seen most of the time -- namely, upright.

Watch  Video The Thatcher Effect Explained

Watch  Video Original Thatcher Demonstration

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People organize what they look at into a meaningful "whole", a "take" that gives meaning to what people are observing.

When a situation is ambiguous, people can easily differ in their perception of the situation. An identical object can be understood as a pedestal or two people, an old woman or a young lady, a young lady or a sax player, two people or one person, or a duck or a rabbit. Some people are able to alter their "take" while others struggle to do so.

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When a situation contains conflicting information, people can misperceive the situation. Identical center-circles appear differently sized, horizontal parallel lines are perceived as sloping, and nonexistent black dots are seen in linear crosshairs.

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When a situation closely fits expectations, people can gloss over discrepancies. What is expected is what is seen, not what is actually present in the situation.


 Learn more about Visual Perception   

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Try these tests of business logos, which are based on the principles of perception discussed in the Visual Resources on this webpage.

What do you see in each logo? Study each logo, and then read the answer.

These tests are quick, and can be shown to a jury or used with witnesses to demonstrate limits to observation and judgment, awareness, memory and perception.

What do you see in the TOSTITOS logo?

If you look at the center of this logo, you can see two people enjoying a Tostitos chip with a bowl of salsa. This logo conveys an idea of people connecting with each other.


What do you see in the FORMULA 1 logo?

At first, this logo might not make much sense. But if you look closely, you'll see the number 1 in the space between the F and the red stripes. I also love how this logo communicates a feeling of speed.


What do you see in the MILWAUKEE BREWERS logo?

The Milwaukee Brewers logo is made up of the letters M (on top) and B (below the m). The M and B form the baseball glove.


What do you see in the NORTHWEST AIRLINES logo?

This simple looking logo actually carries a lot of information. You can see the letters N and W, the first two letters of the brand name. What most people don't see is the compass that points to the Northwest.


What do you see in the TOBLERONE logo?

Toblerone is a chocolate-company from Bern, Switzerland. Bern is sometimes called "The City Of Bears", which has been incorporated into the logo. If you look closely, you'll see the silhouette of a bear.


What do you see in the BASKIN ROBBINS logo?

The old logo of Baskin Robbins had the number 31 with an arc above it to reference its 31 flavors. The pink parts of the new logo retain the 31 flavors slogan while helping form part of the company's initials.


What do you see in the FEDEX logo?

Do you see an arrow in the FedEx logo? If you need help in finding the arrow, roll your mouse over the logo.


Have or want a visual resource? email ComCon