Sensitizing Jurors to the Suggestiveness of In-Court Identifications through Expert Testimony and Judicial Instructions
Creators: name: Katzman, Jacqueline A
Publisher: name: OSF Registries
Year: 2022
Subjects: subject: Law and Psychology
subject: Social Psychology
subject: Social and Behavioral Sciences
subject: Psychology
subject: FOS: Psychology
subject: Law
subject: FOS: Law

description: Title

Sensitizing Jurors to the Suggestiveness of In-Court Identifications through Expert Testimony and Judicial Instructions

Design

The experiment has a 2 (ID: In-Court vs. Show-Up) X 2 (Expert Testimony: Stress vs. Stress + Suggestiveness) X 2 (Judicial Instructions: Present vs. Absent) + 1 (No ID control) between-subjects factorial design. 

Hypotheses 
Participants will watch an online video trial about an individual who committed a robbery and was identified via partial finger-print evidence. The trial will vary based upon the nature of the identification evidence, whether there is expert testimony on the suggestiveness of show-up procedures/in-court identifications, as well as whether there is Henderson-style judicial instructions. 

Manipulation checks: 
H1. Participants who viewed testimony in which a show-up identification procedure is present will be more likely to say that the eyewitness identified the defendant before trial via a showup procedure than will participants who viewed testimony in which the eyewitness made an in-court identification.
H2. Participants who viewed testimony in which the expert witness testified about eyewitness stress and the suggestiveness of certain eyewitness procedures will be more likely to indicate that the expert witness testified about how eyewitness stress and the suggestiveness of eyewitness procedures can influence the reliability of identification evidence than participants who viewed testimony in which the expert witness testified about eyewitness stress only.
H3. Participants who watched the trial in which the judge provided Henderson style instructions (i.e., Judicial Instructions Present) will be more likely to indicate that the judge discussed elements of the crime, the standard of proof, and how suggestive eyewitness procedures can lead to eyewitness errors than will participants who viewed versions of the trial in which the judge did not provide Henderson style instructions. 

Target Hypotheses: 
H4. Participants who watched the trial in which the show-up identification procedure was present will be more likely to convict and rate the eyewitness more favorably than participants who watched the trial in which the in-court identification was present.
H5. Identification type will moderate the effectiveness of the expert testimony safeguard. 
H5a. The expert testimony type will have a simple main effect on participants’ ratings of the suggestiveness of the show-up identification procedure, with those who heard expert testimony on both stress and suggestiveness rating the showup as more suggestive than those who heard the expert testimony on stress only. 
H5b. Expert testimony type will not have a simple main effect on participants’ ratings of the suggestiveness of the in-court identification. 
H6. Identification type will moderate the effectiveness of the judicial instruction safeguard. 
H6a. The presence of a judicial instruction on suggestiveness will have a simple main effect on participants’ ratings of the suggestiveness of the show-up identification procedure, with those who heard the judicial instruction rating the show-up more suggestive than those who did not hear the instruction. 
H6b. The presence of a judicial instruction will not have a simple main effect on participants’ ratings of the suggestiveness of the in-court identification. 
H7. Participants who view the trial in which the in-court identification or show-up identification is present will be more likely to convict than participants who view the trial in which no identification is present (the control condition). 

Methods 

Independent Variables 
1. Identification 
a. Levels: In-court vs Showup 
b. Design: between-subjects 
2. Expert Testimony 
a. Levels: Stress vs Stress + Suggestiveness
b. Design: between-subjects 
3. Judicial Instructions
a. Levels: Present vs. Absent
b. Design: between-subjects

Dependent Variables 
1. Case Judgments 
a. Guilt (dichotomous: guilty, not guilty) 
b. Confidence in guilt decision (101-point scale) 
c. Probability that the defendant committed the crime (101-point scale) 
d. Strength of each side’s case (7-point scales: 1= strongly disagree, 7= strongly agree) 
i. “The prosecution’s case was strong.” 
ii. “The prosecution did not have a lot of evidence of the defendant’s guilt.” 
iii. “The defense’s case raised a reasonable doubt about the defendant’s guilt.”
iv. “The defendant was guilty of the crime of which he was accused.” 

2. Evaluation of the Eyewitness (“How ___ was the eyewitness that was presented during trial?”; 7-point scales: 1= not at all, 7=extremely)
a. Credible 
b. Honest 
c. Confident 
d. Intelligent 
e. Certain 
f. Believable
g. Reliable
h. Accurate
i. Perceptive

3. Procedural Suggestiveness *Only presented if show-up identification is present; **Only presented if in-court identification is present 
a. “The show-up identification procedure was fair.” (7-point scales: 1= strongly disagree, 7= strongly agree)* 
b. “The show-up identification procedure was suggestive.” (7-point scales: 1= strongly disagree, 7= strongly agree)*
e. “The in-court identification procedure was fair.” (7-point scales: 1= strongly disagree, 7= strongly agree)** 
f. “The in-court identification procedure was suggestive.” (7-point scales: 1= strongly disagree, 7= strongly agree)** 

4. Manipulation Checks 
a. Identification type: “Select the choice that best represents what the witness did in the trial. The eyewitness…” (dichotomous: Identified the defendant by pointing to him during the trial, Identified the defendant before trial via a showup procedure)
b. Expert testimony type: “Select the choice that best represents what the expert said in the trial. The expert witness explained that…” (dichotomous: eyewitness stress can influence the reliability of identification evidence, eyewitness stress and suggestive eyewitness procedures can influence the reliability of identification evidence)
c. Judicial Instructions presence: “Select the choice that best represents what the judge said in the trial. The judge discussed…” (dichotomous: Elements of the crime and the standard of proof, Elements of the crime, the standard of proof, and how suggestive procedures can lead to eyewitness errors)

5. Participant Demographics 
a. Gender 
b. Age 
c. US Citizenship Status 
d. Race/ethnicity 
e. Political Views (Liberal to Conservative) 
f. Served on a jury 

Participants 
1. Sample: A sample of 855 participants is sufficient to detect a medium effect (d=.4) with power = .80 and p &lt; .05. To account for manipulation check failure, we will recruit an additional 25%, for a total of 1,069 participants. To appropriately power the logistic regression would require thousands of participants so we have included a continuous measure of guilt that will be appropriately powered to test with an ANOVA. 
2. Recruitment: We will recruit participants from Amazon’s Mechanical Turk (MTurk). MTurk is an online crowdsourcing platform through which “requesters” post tasks that “workers” complete for payment. 
3. Compensation: $5.00 

Exclusion Criteria 
1. Demographics: Participants must be jury eligible. Therefore, participants who are younger than 18 years old or are not U.S. citizens will be excluded. 
2. We will exclude participants who completed the study in an impossibly short amount of time, failed manipulation checks, or provided nonsensical responses (e.g., all responses are the same number). However, if more participants fail manipulation checks than we expect (25%), and if the inclusion or exclusion of those participants does not change our pattern of results, we may choose to retain those participants so as not to sacrifice our power.

Materials 
Trial Video. Participants will view a video-recorded mock trial. The mock trial involves an armed robbery, in which the defendant was initially identified by the police via fingerprint evidence. The trial includes opening jury instructions; opening statements from both attorneys; testimony from an eyewitness and a police officer; expert testimony; closing arguments; and closing jury instructions. The trial will vary in the nature of the identification (in-court, show-up), the content of the expert testimony (stress, stress + suggestiveness), and the presence of judicial instructions on the suggestiveness of certain eyewitness procedures (present, absent) 
a. Identification: In the “in-court” condition, participants will watch a video trial in which the eyewitness identifies the defendant as the perpetrator of the crime. In the “show-up” condition, the identification will be described as a show-up in which the eyewitness positively identified the suspect before trial. 

b. Expert Testimony: In the “stress” condition, the eyewitness expert will only testify about the relationship between stress and eyewitness accuracy. In the “stress + suggestiveness” condition, an eyewitness expert will testify about the suggestiveness of the identification procedures used (i.e., absence of known innocent fillers, absence of instructions, that the suspect is in custody, etc.). 

c. Judicial Instructions: In all conditions, the judge will provide standard instructions at the end of the trial. In the “present” condition, the judge will provide research-based, case-specific Henderson style instructions about the unreliability of procedures that fail to properly instruct witnesses, do not contain fillers, and suggest that the suspect/defendant is in custody.

Procedure 
Participants will complete the entire study online in Qualtrics survey software. They will view the advertisement for the study on MTurk and follow a link to participate in Qualtrics. They will then read the informed consent which explains the purpose, benefits, and risks of participating in the study. If they consent to participate, they will then view the video-recorded mock trial. The survey software will randomly assign them to one of the nine versions of the mock trial. They will then complete the post-trial questionnaire and a demographics survey. The study should take approximately forty-five minutes to complete. Upon completion of the study, the survey software will provide participants with a random identification number for the purposes of compensation. 

Analysis Plan 
Confirmatory Analyses: The main dependent variables of interest are whether the participants indicate that they would vote to convict the defendant and their estimates of the probability that the defendant committed the robbery. We will use a binary logistic regression to predict verdicts and the other dichotomous variables from the full model: 2 (Identification: In-court vs. Showup) x 2 (Expert testimony: Stress vs. Stress + Suggestiveness) x 2 (Judicial Instructions: Present vs. Absent) between-subjects factorial design. Full-model ANOVAs will be used to analyze continuous variables. 
Factor analysis using PAF and varimax rotation will be used to analyze the factor structure of participants’ ratings of the eyewitness, strength of the case, and the suggestiveness of the procedure. Items loading &gt; .4 will be subjected to a reliability analysis. If deleting items improves the Cronbach’s alpha for the scale, they will be deleted. The remaining items will be averaged to form a scale that measures participants’ perceptions of the eyewitness, the strength of the case, and the suggestiveness of the procedures. We will use ANOVAs to assess the effects of the manipulated variables these continuous dependent variables. 
We will use the main effect and interactions stated below to test the indicated hypotheses. In addition to these hypotheses, we will also conduct other analyses, including simple effects tests for significant interactions, as appropriate. 
Manipulation Checks 
H1: (main effect) 
a. Independent Variable: Identification (In-court vs Showup) 
b. Dependent Variable: “Select the choice that best represents the version of the trial that you saw. The eyewitness…” (dichotomous: Identified the defendant by pointing to him during the trial, Identified the defendant before trial via a showup procedure)
c. Direction: Participants will be more likely to indicate “Identified the defendant before trial via a showup procedure” when the identification was a showup than when it was an in-court ID. 
H2: (main effect) 
a. Independent Variable: Expert Testimony (Stress vs. Stress + Suggestiveness) 
b. Dependent Variable: Select the choice that best represents what the expert said in the trial. The expert witness explained that…” (dichotomous: eyewitness stress can influence the reliability of identification evidence, eyewitness stress and suggestive eyewitness procedures can influence the reliability of identification evidence)
c. Direction: Participants who viewed testimony in which the expert witness testified about eyewitness stress and the suggestiveness of certain eyewitness procedures will be more likely to indicate that the expert witness testified about how eyewitness stress and the suggestiveness of eyewitness procedures can influence the reliability of identification evidence than participants who viewed testimony in which the expert witness testified about eyewitness stress only.
H3: (main effect) 
a. Independent Variable: Judicial Instructions (Present vs. Absent)
b. Dependent Variable: “Select the choice that best represents what the judge said in the trial. The judge discussed…” (dichotomous: Elements of the crime and the standard of proof, Elements of the crime, the standard of proof, and how suggestive procedures can lead to eyewitness errors)
c. Direction: Participants who watched the trial in which the judge provided Henderson style instructions (i.e., Judicial Instructions Present) will be more likely to indicate that the judge discussed elements of the crime, the standard of proof, and how suggestive procedures can lead to eyewitness errors than will participants who viewed versions of the trial in which the judge did not provide Henderson style instructions.
H4: (main effect) 
a. Independent Variable: Identification (Incourt vs Showup)
b. Dependent Variable: Guilt (dichotomous: guilty, not guilty)
c. Direction: Participants who watched the trial in which the in-court identification was present will be more likely to convict and rate the eyewitness more favorably than participants who watched the trial in which the show-up identification procedure was present.
H5: (interaction and simple main effects) 
a. Moderators: Identification (Incourt vs Showup)
b. Independent Variable: Expert testimony 
c. Dependent Variable: Guilt (dichotomous: guilty, not guilty); Probability of Commission, Evaluation of the Eyewitness, Suggestiveness 
d. Direction: The type of identification will affect the effectiveness of the expert testimony safeguard on our dependent variables. When participants hear evidence of a show-up identification, those who do not hear expert testimony about procedural suggestiveness will be more likely to convict and rate the eyewitness more favorably than will participants who hear expert testimony on suggestiveness (H5a). When participants hear evidence of an in-court identification, there will be no simple main effect of expert testimony type on participants’ decisions (H5b).
H6: (interaction and simple main effects) 
a. Moderators: Identification (Incourt vs Showup)
b. Independent Variable: Judicial Instruction 
c. Dependent Variable: Guilt (dichotomous: guilty, not guilty); Probability of Commission, Evaluation of the Eyewitness, Suggestiveness 
d. Direction: The type of identification will affect the effectiveness of the judicial instruction safeguard on our dependent variables. When participants hear evidence of a show-up identification, those who do not hear judicial instruction about procedural suggestiveness will be more likely to convict and rate the eyewitness more favorably than will participants who hear a judicial instruction on suggestiveness (H6a). When participants hear evidence of an in-court identification, there will be no simple main effect of judicial instruction on participants’ decisions (H6b).
H7: (main effect) 
a. Independent Variable: Identification (None vs. Incourt/no safeguard vs Showup/no safeguard)
b. Dependent Variable: Guilt (dichotomous: guilty, not guilty)
c. Direction: Participants who view the trial in which the in-court identification or show-up identification is present but neither expert testimony or judicial instruction on procedural suggestiveness is present will be more likely to convict than participants who view the trial in which no identification is present (the control condition). 

Data Handling 
1. Missing Data: Pairwise Deletion 
2. Material Assumption Checks: See Section 4.
3. Multiple tests correction: We will use post hoc tests only when there is a significant omnibus interaction. We will not correct alpha values for multiple comparisons (e.g., Bonferroni, etc). 
Data Collection 
Data collection has not begun. Stimulus materials have been created. Data collection is expected to begin April 2022.