Forensic evidence identification technology

Author: Li Qiongyao
Publisher:
Publishing Date: 2005-01-01
Features: The General Provisions Chapter of the "Criminal Procedure Law of the People's Republic of China" stipulates: "People's Courts, Procuratorates, and Public Security Organs must rely on the masses when conducting criminal proceedings, and must base their judgments on facts and legal standards." In Chapter 5 of the General Provisions, it is explicitly stated: "All facts that help to establish the truth of a case are evidence. Evidence includes the following seven types: (1) Physical evidence and documentary evidence; (2) Witness testimony; (3) Victim statements; (4) Confessions and explanations of suspects and defendants; (5) Expert opinions; (6) Forensic examination and inspection records; (7) Audio-visual materials. All evidence must be verified and confirmed before it can be used as the basis for a verdict." Physical evidence is one of the main components of evidence. It refers to objective facts that are submitted to the competent court after being investigated, examined, collected, and scientifically verified in accordance with legal procedures to confirm the truth of an unverified case. Physical evidence exists as tangible objects with specific sizes, shapes, and distribution ranges, and is a subject with strict legal and rigorous scientific properties.
The scientific field of physical evidence identification in China was established in the mid-20th century. After more than 50 years of development and growth, it has now become highly mature. With the accumulation of experience in handling cases and the continuous updating of technical equipment, numerous new research achievements have been recognized with national science and technology progress awards and have proven effective in physical evidence identification and case handling. These include DNA analysis, fingerprint input and automatic recognition systems, and the creation of infrared computer retrieval spectral libraries for trace physicochemical evidence.
The author has carefully summarized his extensive experience in physical evidence identification research and case handling, absorbing the rich insights of domestic and international peers to write this book. It aims to systematically and comprehensively introduce the basic knowledge of toxicological physical evidence, drug physical evidence, forensic physical evidence, trace physical evidence, fingerprint physical evidence, DNA analysis technology, and various trace physicochemical evidence. This includes the types, classification, chemical structures, characteristics, and extraction, purification, and separation methods of physical evidence, with a focus on the identification methods and techniques of physical evidence. The book provides over a thousand spectral diagrams and charts, making it a practical reference tool for judicial, criminal technical personnel, and analytical testing workers. It is also a teaching reference book for university and college students, particularly those in law and politics-related fields.
Comrade Jiang Xianjin, Vice Minister of Public Security who once held long-term leadership positions in national public security science and technology, has personally written the preface to this book, encouraging all those engaged in physical evidence identification to continuously summarize and advance, making greater contributions to safeguarding social security and protecting the cause of socialist construction. During the writing process, the author also received enthusiastic support and assistance from many colleagues: Ji Anquan and Liu Kuihui wrote Chapter 4, Cui Jiagui wrote Chapter 5, and Deng Zhenhua, Yang Shiyun, Pan Qing, Liu Guangting, Tian Baozhong, Ai Kangyun, Liu Huan, and Yan Zhenyu contributed to several chapters, significantly enriching the book. Gratitude is extended to all of them!