Abstract
The present study presents one of the first investigations of the effects of accomplice witnesses and jailhouse informants on jury decision-making. Across two experiments, participants read a trial transcript that included either a secondary confession from an accomplice witness, a jailhouse informant, a member of the community or a no confession control. In half of the experimental trial transcripts, the participants were made aware that the cooperating witness providing the secondary confession was given an incentive to testify. The results of both experiments revealed that information about the cooperating witness’ incentive (e.g., leniency or reward) did not affect participants’ verdict decisions. In Experiment 2, participant jurors appeared to commit the fundamental attribution error, as they attributed the motivation of the accomplice witness and jailhouse informant almost exclusively to personal factors as opposed to situational factors. Furthermore, both experiments revealed that mock jurors voted guilty significantly more often when there was a confession relative to a no confession control condition. The implications of the use of accomplice witness and jailhouse informant testimony are discussed.
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Notes
The power to detect this very small effect of incentive was admittedly low (1 − β = .10). One alternative explanation that could account for why participant juror verdicts decisions were not influenced by incentive may be that they did not remember there was an incentive. To address this question 28 additional participants participated in the Jailhouse Incentive Type and were asked to indicate in a free recall test whether there was there an incentive. If the participants said there was then they were asked to indicate what the incentive was. Of the 28 additional participants 17 or 61% voted guilty (approximating well the percentage reported for this condition in Experiment 1). Importantly, all but three participants remembered the incentive and were able to recall details about the incentive. Thus, we do not believe that the pattern of results reported in The College Sample can be attributed to the fact that participants simply failed to remember that there was an incentive.
Here again, power to detect the small effect of Incentive was admittedly low (1 − β = .21).
References
Bloom, R. M. (2002). Ratting: The use and abuse of informants in the American justice system. Westport, CT: Praeger Publishers.
Bornstein, B. H. (1999). The ecological validity of jury simulations: Is the jury still out? Law and Human Behavior, 23, 75–91.
Cassidy, R. M. (2004). Soft words of hope: “Giglio, accomplice witnesses, and the problem of implied inducements. North Western University Law Review, 98, 1–43.
Cutler, B. L., Dexter, H. R., & Penrod, S. D. (1990). Nonadversarial methods for sensitizing jurors to eyewitness evidence. Journal of Applied Social Psychology, 20, 1197–1207.
Dill, W. R. (1964). Desegregation or Integration? Comments about Contemporary Research on Organizations. In W. W. Cooper et al. (Ed.), New perspectives in organization research (pp. 39–52). New York: Wiley.
Giglio v. United States, 405 US 150 (1972) 405 US 150.
Gilbert, D. T., & Malone, P. S. (1995). The correspondence bias. Psychological Bulletin, 117, 21–38.
Greene, E. (1988). Judge’s instruction on eyewitness testimony: Evaluation and revision. Journal of Applied Social Psychology, 18, 252–276.
Kassin, S. M., & Gudjonsson G. (2005). The psychology of confession evidence: A review of the literature and issues. Psychological Science in the Public Interest, 5, 33–67.
Kassin, S. M., & McNall, K. (1991). Police interrogations & confessions: Communicating promises and threats by pragmatic implication. Law and Human Behavior, 15, 233–251.
Kassin, S. M., & Neumann, K. (1997). On the power of confession evidence: An experimental test of the “fundamental difference” hypothesis. Law and Human Behavior, 21, 469–484.
Kassin, S. M., & Sukel, H. (1997). Coerced confessions and the jury: An experimental test of the “harmless error” rule. Law and Human Behavior, 21, 27–46.
Kassin, S. M., & Wrightsman, L. S. (1980). Prior confessions and mock juror verdicts. Journal of Applied Social Psychology, 10, 133–146.
Kassin, S. M., & Wrightsman, L. S. (1981). Coerced confessions, judicial instruction, and mock juror verdicts. Journal of Applied Social Psychology, 11, 489–506.
Katzev, R. D., & Wishart, S. S. (1985). The impact of judicial commentary concerning eyewitness identifications on jury decision making. Journal of Criminal Law & Criminology, 76, 733–745.
Mazur, E. P (2002). Rational expectations of leniency: Implicit plea agreements and the prosecutor’s role as a minister of justice. Duke Law Journal, 51, 1333.
Oakes, W. (1972). External validity and the use of real people as subjects. American Psychologist, 27(October), 959–962.
Peterson, R. A. (2001). On the use of college students in social science research: Insights from a second-order meta-analysis. Journal of Consumer Research, 28, 450–461.
Rappold, S. (2005). Jailhouse informers: A risky bet. The Gazette Nov 20.
Ross, L. (1977). The intuitive psychologist and his shortcomings: Distortions in the attribution process. Advances in Experimental Social Psychology, 10, 174–221.
Schultz, D. P. (1969) The human subject in psychological research. Psychological Bulletin, 72(September), 214–228.
Sears, D. O. (1986). College sophomores in the laboratory: Influences of a narrow data base on social psychology’s view of human nature. Journal of Personality and Social Psychology, 51(September), 515–530.
Simon, D., & Holyoak, K. J. (2002). Structural dynamics of cognition: From consistency theories to constraint satisfaction. Personality and Social Psychology Review, 6, 283–294.
United States v. Singleton, 144 F.3d 1343 (10th Cir. 1998).
Weick, K. E. (1967). Organizations in the Laboratory. In V. H. Vroom (Ed.), Methods of organizational research (pp. 1–56). Pittsburgh: University of Pittsburgh Press.
Acknowledgements
The authors give thanks to Aurora Torres and Michael P. Toglia for helpful comments on earlier versions of this manuscript. Grateful appreciation is also expressed to Adam Shipley, Michelle Davis, Daniel Neuschatz, Anita Quinlivan, and Christy Gray for their assistance during the data collection phase of this experiment.
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Neuschatz, J.S., Lawson, D.S., Swanner, J.K. et al. The Effects of Accomplice Witnesses and Jailhouse Informants on Jury Decision Making. Law Hum Behav 32, 137–149 (2008). https://doi.org/10.1007/s10979-007-9100-1
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DOI: https://doi.org/10.1007/s10979-007-9100-1