中国人民警察大学学报

刑事物证溯源是精准打击犯罪的关键环节，然而对于缺乏生物特征信息的金属类物证，其溯源始终是法庭科学面临的瓶颈。引入地球化学中成熟的铜（Cu）同位素分析技术，构建一种高精度的金属物证溯源方法。重点阐述基于多接收器电感耦合等离子体质谱（MC-ICP-MS）的Cu同位素测试技术，包括样品的高温高压消解、AG MP-1M阴离子交换树脂分离纯化及标准—样品交叉法与内标法相结合的仪器质量歧视校正方案。在此基础上，构建该技术在电缆盗窃案、涉枪案件、交通事故现场重建及环境污染刑事调查等警务场景中的溯源模型与应用路径。研究证实，Cu同位素作为一种稳定的“地球化学指纹”，能有效区分不同来源的金属材料，为物证与嫌疑源之间的关联认定提供证据。

Tracing the origin of criminal physical evidence is a key step in accurately combating crime, yet it remains a persistent challenge in forensic science since such metallic evidence lacks biological markers. Our study incorporates well-established copper(Cu) isotope analysis from geochemistry to develop a high-precision tracing method for metallic evidence. This paper provides a focused elaboration on Cu isotope measurement techniques based on multi-collector inductively coupled plasma mass spectrometry(MC-ICP-MS), detailing high-pressure/high-temperature sample digestion, purification with AG MP-1M anion exchange resin, and a mass bias correction strategy that integrates standard-sample bracketing with internal standardization. Building on this foundation, tracing models were established and applied in four key policing scenarios: cable theft, firearm-related crimes, traffic accident reconstruction, and criminal investigations of environmental pollution. Our study confirms that Cu isotopes can serve as a stable “geochemical fingerprint” to effectively distinguish metal materials from different sources, providing robust scientific evidence for linking physical evidence to suspected origins.