Social Psychological Factors in Eyewitness Identification: Social Influence in Choosing Behavior

在美国，错误的目击者辨认是造成大多数错误定罪的原因（Wells等人，1998；Warden等人，2001）。在一项对86起已知错误定罪案件的分析中，涉及证人证词的46起案件中有14起有多名证人作证（Warden et al., 2001）。为什么多个目击者会指认错同一个人？过去的研究表明，记忆不仅受到认知变量的影响，也受到社会变量的影响，特别是在记忆不确定或编码不良的情况下（Wather et al., 2002）。研究人员已经证明，讨论犯罪的两个目击者可以影响彼此对事件的记忆（例如，Gabbert et al., 2003）。然而，很少有研究调查了共同证人信息对目击证人身份选择的影响。在一项初步研究中，我们证明了学习了共同证人的列队决策（即选择或拒绝列队）的参与者在从列队中选择时受到共同证人的决定的影响。使用社会和认知心理学理论来告知我们的研究，这个项目包括两个研究，旨在探索何时以及为什么社会信息影响目击者的阵容选择。在这两项研究中，目击证人都会在同盟者作为共同目击证人的情况下观看犯罪。在第一个研究中，我们将探讨目击证人的记忆强度（或感知强度）与共同证人的记忆相比是否会影响目击证人是否可能遵守共同证人的决定。在第二个研究中，我们将探讨共同证人的信心（以及证人对共同证人信心的信念）在证人是否会受到共同证人阵容决策信息的影响中的作用。通过这些研究，我们将能够确定何时以及为什么共同证人信息会影响目击者的识别决定。

Mistaken eyewitness identification is responsible for the majority of wrongful convictions in the United States (Wells et al., 1998; Warden et al., 2001). In one analysis of 86 cases of known wrongful conviction, multiple eyewitnesses testified in 14 of the 46 cases involving eyewitness testimony (Warden et al., 2001). Why would multiple eyewitnesses identify the same wrong person? Past research has demonstrated that memory is not only affected by cognitive variables, but social variables as well, especially in those situations in which the memory is not certain or poorly encoded (Wather et al., 2002). Researchers have shown that two eyewitnesses who discuss the crime can affect each other's memories for the event (e.g., Gabbert et al., 2003). However, very few studies have examined the effect of co-witness information on an eyewitness's identification choices. In a pilot study, we demonstrated that participants who learned the lineup decision of a co-witness (i.e., to choose from or reject the lineup) were influenced by the co-witness's decision when choosing from the lineup. Using social and cognitive psychological theory to inform our research, this project consists of two studies designed to explore when and why social information influences an eyewitness's lineup choice. In both studies, an eyewitness will view a crime with a confederate acting as a co-witness. In the first study, we will explore whether the strength (or perceived strength) of an eyewitness's memory compared to the memory of the co-witness affects whether an eyewitness is likely to conform to the decision of the co-witness. In the second study, we will explore the role of the co-witness's confidence (and the eyewitness's beliefs about the co-witness's confidence) in whether an eyewitness will be influenced by co-witness lineup decision information. Through these studies, we will be able to ascertain when and why co-witness information will affect an eyewitness's identification decision.