2.  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.

3.  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.

4.  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

5. 1 2 3
4 5 6

6.  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

7.  Witnesses would
see a suspect
photo one at a
time in a format
such as this.
1

8.  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.

9.  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.

10.  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.

11.  To identify the
suspect, the witness
confirms the name
and color of the
shape.
 Example: “Blue Star”

12.  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.

13.  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.

14.  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.

15.  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%.

17.  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.

18.  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.

19.  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.

20.  Sponsor: Trent Terrell Ph.D
 Co-researchers:
› Thomas Via
› Kristina Zufall
› Hope Underwood