Slideshow: A New Approach to Suspect Lineups

Brooke CoxTaylor Kleshick

What Is Eyewitness Memory?

After viewing a crime or event, eyewitnesses are asked to identify the perpetrator from a list of suspects.

Unfortunately, eyewitness memory is unreliable, and lineups often contain some form of bias.

Current Lineups

Currently there are two lineups styles that law enforcement can use with witnesses:› Simultaneous› Sequential

Witnesses can also be shown only a picture of the suspect. This is called a Showup.

Simultaneous

Simultaneous- all suspects featured in the lineup are shown at once.› Higher identification rate: Both positive

and false identification› Potential for comparative judgments—

choosing the face who looks “most like” the perpetrator

Simultaneous

1 2 3

4 5 6

Sequential

Sequential- The people featured are shown one at a time, and the witness must say whether or not the person currently shown is the perpetrator. › Lower Identification rate: Both positive and

false identifications

Sequential

Witnesses would see a suspect photo one at a time in a format such as this.

1

Current Practices

Most police municipalities do not have formal rules or guidelines about which type of lineup to use, or how to interact with witnesses.

Most memory researchers recommend using a sequential lineup.

The prevailing theory is that sequential presentation reduces false identifications, without concurrently reducing true identifications.

Slideshow

In the present research, we propose a third type of lineup--slideshow.

The witness can view each face as many times as needed, however only one face is on the screen per time.

Each picture is shown for 6 seconds before the presentation automatically moves on to the next picture.

The slideshow runs on a continuous loop until the witness makes a decision.

Slideshow

The witness picks a starting point at random.› This is accomplished by selecting a card at

random with a colored shape on it.› This shape corresponds to one of the

shapes we have associated with each of the suspects.

› When no picture is obviously first or last we can control for possible sequence effects.

Slideshow

To identify the suspect, the witness confirms the name and color of the shape.

Example: “Blue Star”

Hypothesis

The slideshow lineup will produce the same number of correct IDs as the simultaneous lineup.› Current thinking is that simultaneous

lineups produce more IDs because witnesses have time to compare all the faces and “pick the closest one”.

› We hypothesize that the benefit will still exist with multiple exposures but no opportunity to directly compare faces.

Our Research

101 general psychology students from the University of Mary Hardin-Baylor participated in our experiment.

The experiment was double-blind› Neither witnesses nor proctors knew who

the suspects were in the lineups.

Our Research

We split participants into 3 groups:› Simultaneous Lineups(31)› Sequential Lineups (32)› Slideshow Lineups (38)

We showed a 45 second video of a mock car jacking to all participants.

They were given two 5-minute questionnaires to create a delay between the video and the lineup.

Our Research

A target present lineup was shown containing 6 suspects.› Target present means the true suspect was

present in the lineup. The participant’s selection was

accompanied by a self-evaluated confidence level based on their selection.› The confidence ratings varied from 0-

100%.

Results

Conclusions

The simultaneous and slideshow lineups produced a similar rate of correct identifications, supporting our hypothesis.

The sequential lineup produced a mean correct ID rate of 31%.› This challenges previous findings

suggesting that sequential presentation of a lineup does not significantly reduce the likelihood of correct identifications.

Future Research

So far, we have supported the hypothesis that simultaneous and slideshow presentation of a target-present lineup produces similar results.

Next, we need to see what happens with target-absent lineups.

Future Research

We hope that slideshow presentation of a target-absent lineup will lead to fewer false identifications than simultaneous presentation of a target-absent lineup.

This would create a lineup format that merges the benefits of both simultaneous and sequential presentation.

Acknowledgments

Sponsor: Trent Terrell Ph.D Co-researchers:

› Thomas Via› Kristina Zufall› Hope Underwood