slideshow lineup

of 20 /20

Upload: brookecox

Post on 05-Jul-2015




1 download


Page 1: Slideshow lineup
Page 2: Slideshow lineup

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.

Page 3: Slideshow lineup

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


Page 4: Slideshow lineup

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


Page 5: Slideshow lineup

1 2 3

4 5 6

Page 6: Slideshow lineup

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

Page 7: Slideshow lineup

Witnesses would

see a suspect

photo one at a

time in a format

such as this.


Page 8: Slideshow lineup

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.

Page 9: Slideshow lineup

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.

Page 10: Slideshow lineup

The witness picks a starting point at


› 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


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

Page 11: Slideshow lineup

To identify the suspect, the witness

confirms the name

and color of the


Example: “Blue Star”

Page 12: Slideshow lineup

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.

Page 13: Slideshow lineup

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.

Page 14: Slideshow lineup

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.

Page 15: Slideshow lineup

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


› The confidence ratings varied from 0-100%.

Page 16: Slideshow lineup
Page 17: Slideshow lineup

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.

Page 18: Slideshow lineup

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.

Page 19: Slideshow lineup

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.

Page 20: Slideshow lineup

Sponsor: Trent Terrell Ph.D


› Thomas Via

› Kristina Zufall

› Hope Underwood