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Measuring knowledge of the insanity defense: scale construction and validation
Tarika Daftary-Kapur1, Jennifer L Groscup, Maureen O'Connor
1Vera Institute of Justice, 233 Broadway, New York, NY 10279, USA.. tdaftary@gmail.com
Behavioral Sciences & the Law
|January 26, 2011
Summary
Developing a scale to assess laypersons' knowledge of the insanity defense is crucial for ensuring fair jury decisions. This research created and validated a tool to measure understanding and its impact on verdicts.
Area of Science:
- Forensic Psychology
- Legal Psychology
- Jury Decision-Making
Background:
- Defendants pleading not guilty by reason of insanity (NGRI) face challenges in obtaining impartial juries due to social prejudice.
- Jury impartiality can be affected by jurors' attitudes and knowledge regarding the insanity defense.
Purpose of the Study:
- To develop and validate a scale measuring laypersons' knowledge of the insanity defense.
- To examine how knowledge of the insanity defense influences jury decision-making.
Main Methods:
- Two studies were conducted to construct and refine the scale.
- Scale items were based on established insanity defense myths.
- Reliability and construct validity were assessed and improved across studies.
Main Results:
- The scale demonstrated improved reliability and construct validity after revisions.
- The developed scale showed acceptable predictive validity for insanity defense verdicts.
Conclusions:
- A reliable and valid scale for assessing knowledge of the insanity defense has been developed.
- This scale can be a valuable tool for understanding factors influencing jury impartiality in NGRI cases.
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