物证鉴定范式发展(三):DNA特征客观似然比范式  

Forensic Paradigm Development.Part 3:Objective LR Paradigm of DNA Features

作　　者：王桂强 WANG Guiqiang(Institute of Forensic Science,Ministry of Public Security,Beijing 100038,China)

机构地区：[1]公安部鉴定中心,北京100038

出　　处：《刑事技术》2024年第6期551-565,共15页Forensic Science and Technology

摘　　要：DNA特征客观似然比范式是关于DNA物证特征结果证据意义解释的理论和方法。它是物证鉴定贝叶斯似然比范式的典型代表。DNA特征结果客观似然比(LR)是在通常分别代表控辩双方主张的两个对立命题条件下,基于模型和数据定量分配的DNA特征结果出现概率的比值。命题层级包括亚–亚来源、亚来源、斑痕来源和行为层级。DNA特征结果LR表达了DNA结果对控辩双方命题的相对支持方向和强度,为决策者确定有争议的命题事实提供了量化证据价值。决策者基于DNA结果LR意见,或基于LR经贝叶斯定律导出的命题后概率,结合案件其他证据排除合理怀疑地确定命题事实。DNA特征客观LR范式在科学逻辑以及意见的形成、表述、理解和推理应用方面完全不同于人们已经习惯的传统范式,这给鉴定人和决策者提出了新的要求和挑战。The objective likelihood ratio(LR)paradigm of DNA feature is the theory and method for interpreting the evidential significance of DNA analysis findings.It is a typical representative of the forensic Bayesian likelihood ratio paradigm.The DNA feature’s objective LR is the ratio of the probability of DNA feature findings quantitatively assigned based on model and data,in the context of two alternative propositions typically advocated by both of the prosecution and defense.The hierarchy of propositions includes the sub-sub source level,sub-sources level,sources level,and activity level.The LR of DNA feature findings expresses the relative support direction and strength of the DNA findings for the propositions of the prosecution and defense,providing quantitative evidence value for decision-makers to determine disputed propositional facts.Decision makers will determine the propositional facts without reasonable doubt,based on the LR opinions of DNA findings or the posterior probability of the propositions derived from LR opinions and Bayesian laws,and combined with other evidence in the case.The DNA feature’s objective LR paradigm is completely different from the traditional paradigm that we are used to in terms of scientific logic,opinion formation,expression,understanding,and reasoning applications,which poses new requirements and challenges for forensic examiner and decision-makers.

关 键 词：物证鉴定 DNA 特征似然比 客观 范式 

分 类 号：DF794[政治法律—诉讼法学]