DOI: 10.3886/icpsr39002.v1
title: Improving Juror Comprehension of Forensic Testimony and Its Effects on Decision-Making and Evidence Evaluation, United States, 2020
title: Version 1

description: Forensic science plays a vital role in the prosecution of criminal matters. Jurors, however, struggle with understanding both the science and statistics that underlie such testimony. Prior research on the effectiveness of jury instructions in training jurors to understand science and scientific testimony has been split, with some studies finding a beneficial effect, some finding no effect, and some finding that they cause jurors to be skeptical even of high-quality testimony. Here, investigators sought to empirically test the effectiveness of an instructional video at improving jurors' ability to detect low-quality forensic testimony. For the purposes of this study, testimony quality was defined based on the Department of Justice's Uniform Language for Testimony and Reports (DOJ ULTR).

The Gender Effects Paper Study Data made available through ICPSR includes data from the Main Study and a second pilot study conducted by researchers. These data were compiled to examine the impact of a forensic expert's gender on jurors' assessments of the quality of the expert's testimony.


There are two additional datasets associated with this study:

Main Study:
Dataset contains survey results from a sample of 509 jury-eligible U.S adults who participated in the Main Study.
Pilot Study:
Dataset contains survey results from a sample of 229 jury-eligible university undergraduates who completed the Pilot Study.
description: The purpose of this study was to evaluate the effectiveness of jury instructions at preparing jurors to correctly identify high and low-quality testimony by forensic experts.
description: To test their hypotheses, the research team developed an instructional video explaining forensic science and the DOJ ULTR guidelines to prepare participants to assess forensic testimony. In the Pilot Study, participants were asked to rate improper statements by a forensic expert, with some participants having watched the instructional video and some responding using only their existing knowledge. In the Main Study, participants were shown a 45-minute mock trial video and asked to assess both the forensic experts themselves and the evidence that they presented. The mock trial video contained either high or low-quality testimony, with the quality determined by adherence to ULTR guidelines.
description: The Gender Effects Paper Study Data includes variables indicating participants' assessments of a mock trial video, including their opinion on whether the defendant was guilty or innocent, their assessment of the testimony's strength and quality, and their perception of the testifying expert (unfriendly vs friendly, disrespectful vs respectful, uneducated vs educated, etc.). These data also include several demographic variables about participants' races and ethnicities, genders, education levels, and political leanings.
description: Main Study -- 641 jury-eligible participants from across the U.S. were recruited using the online recruitment platform Prolific. 509 were included in the final sample after completing the study and passing attention/comprehension checks.
Pilot Study -- 289 participants were recruited from a university undergraduate sample. 229 were included in the final sample after completing the study and passing attention/comprehension checks.
Gender Effects Paper Study -- This study combined data from the Main Study with new data from a second pilot study. 896 participants were recruited from a university undergraduate sample for the second pilot study, with 562 included in the final sample after screening by eligibility criteria, survey completion, and correct attention/comprehension checks. The data taken from the Main Study were filtered to exclude control group participants and the small number of participants who marked a gender other than male or female. The final sample size after these exclusions was 497. Please refer to the syntax files included with the data and documentation for more details on how the Main Study data were utilized in the Gender Effects Paper Study.
description: Datasets: 
DS1: Gender Effects Paper Study Data
description: Jury-eligible adults in the United States.
description: web-based survey