The Role of Diagnostic vs. Non-Diagnostic Facial Features in Eyewitness Identification

无辜嫌疑人被错误地判定犯有他们没有犯下的罪行的问题，以及有罪嫌疑人被错误地释放到社会上的平行问题，在很大程度上可归因于目击者记忆的错误。大量目击者记忆研究的重点是减少对无辜嫌疑人的虚假识别(从而减少他们被错误定罪的可能性)。然而，减少这一不幸错误的方法往往会增加补充性错误，即未能查明有罪嫌疑人的错误。这种权衡可能被认为是可以接受的，但更好的方法将涉及同时减少这两个错误。到目前为止，考虑到这一目标的研究很少，但这是这里提出的研究的目标。特别是，这项研究询问可以做些什么来提高目击者的辨别力(即区分无辜嫌疑人和有罪嫌疑人的能力)。为了回答这个问题，这项研究以一种新的目击者识别理论为指导：诊断特征检测假说。提高目击者记忆程序的辨别能力具有重要的更广泛的影响，因为它将减少对无辜的误认，同时增加对有罪的识别。本项目将集中于三种广泛使用的目击证人识别程序：传统的同时序列(6张脸同时向证人展示)，较新的顺序序列(6张脸一次向证人展示6张脸)，以及出庭程序(只向证人展示一张脸，以做出是/否的决定)。几乎所有警察部门都使用对峙程序(因为这往往是快速推进的调查中唯一的可能性)，近30%的警察部门已经从同时列队程序切换到顺序程序。然而，与之前认为的相反，最近的工作发现，对峙和顺序阵容都不如同时程序(即，与其他两种程序相比，同时程序可以减少对无辜嫌疑人的错误识别，同时增加对有罪嫌疑人的正确识别)。鉴于摊牌程序和顺序排列的常见和可能继续使用，本研究提出了一系列实验，以调查简单和方便的方法，以提高这些目击者识别程序的诊断准确性。

The problem of innocent suspects being mistakenly convicted of a crime they did not commit and the parallel problem of guilty suspects being mistakenly released into society are attributable in no small part to the fallibility of eyewitness memory. A great deal of eyewitness memory research has focused on reducing false identifications of innocent suspects (thereby reducing the chances that they will be wrongly convicted). However, methods that reduce that unfortunate error often have the effect of increasing the complementary error, namely, the error of failing to identify guilty suspects. That tradeoff might be considered acceptable, but a better approach would involve reducing both errors simultaneously. To date, very little research has been conducted with that goal in mind, but it is the goal of the research proposed here. In particular, this research asks what can be done to enhance eyewitness discriminability (i.e., the ability to tell the difference between innocent and guilty suspects). To answer this question, the research is guided by a new theory of eyewitness identification: the diagnostic feature-detection hypothesis. Enhancing the discriminability of eyewitness memory procedures has significant broader impacts because it would decrease misidentifications of the innocent while at the same time increasing identifications of the guilty.This project will focus on three widely used eyewitness identification procedures: the traditional simultaneous lineup (in which 6 faces are shown to the witness simultaneously), the newer sequential lineup (in which the 6 faces are shown to the witness one at a time), and the showup procedure (in which only one face is shown to a witness for a yes/no decision). Virtually all police departments make use of the showup procedure (because it is often the only possibility in a fast-moving investigation), and nearly 30% of police departments have switched from the simultaneous lineup procedure to the sequential procedure. However, contrary to what was previously believed, recent work has found that both the showup and the sequential lineup are inferior to the simultaneous procedure (i.e., the simultaneous procedure can reduce false identifications of innocent suspects while at the same time increasing correct identifications of guilty suspects compared to the other two procedure). Given the common and likely continued use of the showup procedure and sequential lineup, this research proposes a series of experiments to investigate simple and convenient ways to enhance the diagnostic accuracy of these eyewitness identification procedures.