The "Eyes" Have It: Analyzing Eyewitness Testimony

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SWBAT identify how memories can be affected by a variety of factors. SWBAT understand the limitations of eyewitness testimony based on human cognition and memory.

Big Idea

Witness testimony is used in a variety of cases to catch criminals, but how accurate can it really be?

Day 1: Engage

5 minutes

I start each class period in this unit with a warm-up activity that targets forensic science concepts and other skills (observation, problem-solving, etc.) Not only does this get the students in the frame of mind necessary to address the field of forensics, but it also introduces key vocabulary they will use throughout the unit in a more relevant way. In addition, this activity allows students to refine their research skills as they perform quick internet searches to find the correct answers. By using the attached weekly Answer Sheet* and passing it out as they enter the classroom every Monday morning, not only can I save paper, but I can also provide a routine that allows students to begin without prompting, waiting for paper, or asking things such as, "What do we do?" and, "Where do we write our answers?"

For this particular lesson, I have decided to utilize a Trivia Challenge*, in which students use their knowledge of forensics and their research skills to answer an assortment of trivia questions.

After providing about 2-3 minutes to look for the answers, we go over them together and discuss the information provided. I help students to define key terms and providing background knowledge necessary to help students understand the questions. However, I do not spend as extended period of time on this portion, as it is just meant to be an activator and not necessary to understanding the core of the lesson at this time.

*Challenges and answer sheet courtesy of

Day 1: Explore

20 minutes

The next part of the lesson entails a little front loading in order for students to become familiar with the terminology associated with eyewitness testimonies. I review the first two slides with the students, encouraging participation and drawing upon background knowledge as I ask students to provide examples of eyewitness testimonies they have recently seen or heard about on television, in the news, etc.

Next, I explain to the students that in order to provide a good eyewitness testimony, people have to concentrate heavily on what they were able to see and recall. I ask the students to consider how difficult it might be to recall a scene in which a crime may have occurred. After getting a few opinions, I explain the Memory Challenge slides 3-4) in which students will view several pictures for 30 seconds and to try to remember everything they saw, including details about color, size, etc.  

As the students attempt the challenge, I try to influence their memory of the items. I have done this by providing a somewhat distracting timer, and I also talk to them throughout the thirty minutes, making them think this is unintentional on my part. I may say things such as, "Has anyone seen the bathroom pass?"  or "By the way, I posted the grades for your last science test online yesterday." I want to slightly distract them from the task, similar to the way a witness may have several distractions when viewing a crime in action.

After thirty seconds is up, I have them take out a scratch piece of paper and write down all of the items and details they can remember. As they are writing down the items they remember, I again attempt to influence their memory by suggesting two or three items that were not shown, such as comparing the sizes of the rainbow to the pot of gold next to it (which doesn't really exist) , or prompting them to remember to write down the color of the pen (instead of a pencil, which is actually on the slide).  



After giving them about 60 seconds to write down everything they remember, I return to the slide and we go over the correct items. At this time, I ask the students if they added any of the ones I mentioned as they were writing. Undoubtedly, a few will. However, others will catch on to my trick and will throw me under the bus.  This is what I want them to do, because it is a great segue into the discussion (slide 6) on how a person’s memory can be affected by another person.

Before moving on to the discussion, however, I want to get the students thinking about other factors that might affect a person's memory, such as the amount of time someone has to view a particular image or scene. In order to learn more about this, we participate as a class in the Change Blindness Activity (slide 5). In this activity, students view a picture for a selected period of time (which you can adjust) and try to determine changes in the image as it blinks on and off.

Day 1: Explain

60 minutes

Now that students have experienced how slight distractions and suggestions can affect their memory, we will dig deeper into how eyewitness accounts can be affected by a variety of factors.

I hand each student 5 talking chips and post slide 5 on the board. I ask the students, "What factors affect a person's memory and ability to identify a suspect?" Each student must use only two - and only two - of their talking chips to share some insight into the question with the rest of their table group.

After sharing in groups, I call on several random students to provide a response (their own or a partner's) to the class and to explain their thinking. I write their responses on the board in the form of a list.

Next, I play the video clip on slide 6, titled, "Bunny Effect". This short video clip describes how people's memories can be easily influenced by subtle hints that are planted within their environment. 

After viewing, I pass out the "How Accurate Eyewitness Accounts" reading and have students Radio Read the entire article with their table group. Because this is a fast-paced strategy, it allows us to complete it in a reasonable amount of time and continue on to the next activity. However, it results in active participation,  deep thinking, and comprehension of the material from all members of the group.

After viewing the video clip and reading the article, I pose the same question, "What OTHER factors affect a person's memory and ability to identify a suspect?" Again, each student must use only two - and only two - of their talking chips to share some insight into the question with the rest of their table group. I call on students to again share with the class and I add their new responses to the list.

I present the ideas in slide 6 that students have not yet touched on or gained understanding from the reading and/or videos. If time permits, I also play the videos on slides 8 and 9. Each one is approximately 15 minutes in length. Brain Games discusses the intricacies of the human face and how we relate to and remember people's faces. The TedEx video discusses how memories can be distorted and provides an example of this within the scenario of a false accusation.  These are both valuable videos, but may stretch the lesson to three days if discussions following them are particularly rich. If time does not allow for this, these can be assigned for homework, with a short discussion to follow the next day.

Day 2: Elaborate

15 minutes

Now that students have learned more about how their memories can be distorted due to distractions or manipulations, they are starting to feel more confident that they can prevent this from happening within their own brains. I like to challenge them to see if this is the case. 

I explain to the students that we will test their observation skills a bit more. I post a photograph of a crime scene (slides 10-11) and allow two minutes for the students to study the photograph.   I encourage them, again, to pay attention to details and let them know they will be asked ten questions about the crime scene.  Like our first challenge, they are not allowed to take pictures or write anything down . After two minutes is up, I post the questions (slide 12) and have the students write down their answers. Once all students have finished, I post the answers (slide 13) and we review as a class, discussing and referring back to the picture as necessary.

Students will now get a chance to learn how people use their memories to create facial compositions. To learn the associated background knowledge and vocabulary, students will begin with the activity (slide 14), called "The Art of Crime Detection"*. In this interactive, students will view "crimes" taking place and will have to create a composition of the assailants. They will get feedback on their composites as they progress through the interactive. The last section allows students to create a composite of themselves, which is a fun way to see how students see themselves.


*For more information on "The Art of Crime Detection, please watch my video tutorial!

Day 2: Evaluate

45 minutes

As a final activity, I place the students into groups of 2 and ask them to pretend that their partner has just committed a heinous crime and they were the only ones there to witness it. Once I set the stage, I separate partners to opposite sides of the room and have them face away from each other so that they can no longer see each other. Knowing this person has just committed a crime, the student is tasked with creating a facial composite using one of the web-based programs I have provided (slide 15). After they have created their composite, they will take a snapshot or save their image and print it for their partner to see.

After students create their composite, they will complete a Ticket Out the Door by answering the reflection questions (slide 16) on the provided ticket templates.