RR: The Validity of Cartridge Case Comparison Conclusions Under Field-Based Conditions

2009年，国家研究委员会呼吁科学家对法医技术在现实的现场条件下的有效性进行量化。之所以发出这一呼吁，是因为越来越明显的是，在关于广泛的法医技术有效性的知识方面存在着潜在的差距。然而，法医科学的结果往往被视为客观的，因此它们被执法部门和法院接受并使用，甚至更多。该项目将调查和量化枪弹案件比对的有效性，这是一种常用的法医技术。由于这项技术依赖于对发射弹壳的目视检查，因此它是一个主观过程，容易受到人为判断错误的影响。然而，即使这种技术是主观的，如果在各种基于现场的条件下人的判断错误率很低，它仍然可以是一种有效的技术。由于所有的法医结论都包含一定程度的不确定性，本研究可以促进人们对法医科学有效性的理解。该项目将在实地条件下进行对照试验，以解决传统同行审查程序是否在将取证错误传达给执法部门和法院之前有效地发现取证错误，以及取证错误的发生率是否根据不同枪支品牌生产的工具标记的质量而有所不同。该项目的基础是与决策和认知处理相关的心理学理论，它符合对评估法医技术有效性的严格科学测试的呼吁。这项研究带来了科学的方法(包括实验操作)来研究子弹壳比较的有效性，包括这项技术的稳健性(在传统同行审查程序的背景下)和可靠性(在不同的现场条件下)。这项研究有可能通过强调传达法医结论的不确定程度的重要性，同时确定对传统同行审查程序的潜在威胁，从而改变法医科学做法。该项目由美国国家科学基金会和美国国家司法研究所联合资助。

The National Research Council in 2009 called for scientists to quantify the validity of forensic techniques under realistic, field-based conditions. This call was prompted because it is increasingly apparent there are potential gaps in knowledge about the validity of a broad range of forensic techniques. Yet, the results of forensic science are often viewed as objective, and as such they are accepted and used by law enforcement and courts, and beyond. This project will investigate and quantify the validity of fired gun cartridge case comparison, a commonly used forensic technique. Because this technique relies on visual inspection of fired cartridge cases, it is a subjective process that is susceptible to human judgment error. However, even though this technique is subjective, it can still be a valid technique if the rate of human judgment error is low under a variety of field-based conditions. Because all forensic conclusions involve some degree of uncertainty, this research can advance understanding about the validity of forensic science. The project will use a controlled experiment under field-based conditions to address whether conventional peer-review procedures effectively discover forensic errors before they are communicated to law enforcement and the courts, and whether the rate at which forensic errors occur varies based on the quality of toolmarks produced by different firearm brands. The project is grounded in psychological theory related to decision-making and cognitive processing, and it accords with calls for rigorous scientific tests to evaluate the validity of forensic techniques. The research brings scientific methods (including experimental manipulations) to the study of the validity of cartridge case comparisons, including the robustness (in the context of conventional peer-review procedures) and reliability (across different field-based conditions) of this technique. This research has the potential to transform forensic science practices by emphasizing the importance of communicating the degree of uncertainty that characterizes forensic conclusions, while identifying potential threats to conventional peer-review procedures. This project is jointly supported by National Science Foundation and the National Institute of Justice.