A bloody stainless steel kitchen knife, a torn address book, a mobile phone soaked in the basin and a leftover apple core... The murder case in the rental house at the beginning of the century left only a small amount of evidence, making it difficult to remember at that time. Detected. After 23 years, the Shanghai Baoshan Police traveled to Jiangsu, Zhejiang, Shanghai, Anhui and other places, integrating science and technology, data application and investigation work, and continuously and continuously comparing biological samples in the system, and finally cracked the case in February this year. House murder.
Rental house murder case: An apple core guides the direction of investigation
On the evening of December 31, 2001, the Shanghai Baoshan police received a call from the public, saying that their friend was murdered in a rental house in a community in Baoshan. When the police investigated the scene, they found that the deceased, Ms. Huang, 32 years old, had been slashed on the head. It was estimated that the time of death was noon that day. There was a bloody stainless steel kitchen knife at the scene. The police determined that the rental house was the scene of the first crime.
In addition to the murder weapon left by the murderer, the police also found a torn address book, a mobile phone that had been soaked in the basin, and a leftover apple core. The police learned from the caller that the deceased had complex social relationships during his lifetime, and his address book would record the contact information of some friends he frequently interacted with. At the same time, the caller also provided the police with a clue. The deceased never ate apples, but had the habit of peeling apples to entertain guests. After testing, two biological traces were left at the scene. In addition to the deceased himself, the other biological trace probably belonged to the murderer. Based on the above clues, the police focused their investigation on the crime committed by an acquaintance.
On the one hand, the police ruled out the suspicion of the caller through blood type comparison and alibi; on the other hand, the police obtained the last call sign record of the deceased's mobile phone from the communication company, and locked the dial number from a cigarette shop near the crime scene. A public phone in a grocery store. According to the employees of the tobacco store, a nearly 40-year-old man with a thin build, a dark jacket, and an accent from Nantong, Jiangsu Province called at noon that day. Criminal investigation experts drew a simulated portrait based on physical characteristics. The police used this portrait to visit 39 residential buildings in the community where the crime occurred and a 5-kilometer surrounding area, but found nothing.
Simulated portrait of a criminal suspect. Source: Shanghai police
Suspect portrait: Investigators screened occupation from collar
Due to the delay in identifying the portrait, investigators believed that the suspect might not be a nearby resident, so they shifted the investigation direction to the suspect’s occupation. The investigators started from the jacket collar in the simulated portrait and collected a large number of uniform samples that were mainstream in society at that time. Based on the characteristics of the Baoshan area, they speculated on the possible occupation of the suspect: taxi driver, metallurgical worker or construction worker.
investigators spent three months interviewing more than 1,400 taxi drivers with portraits of the suspects; interviewed about 1,000 employees with Nantong accents from metallurgical companies surrounding the crime scene; and visited a property adjacent to the crime scene. More than 100 workers with accents from Nantong area under construction were arranged one by one. On this basis, the police combed through the residence registration and hotel registration information around the crime scene in the past six months, but no clues were found.
In the next 20 years, the Criminal Investigation Detachment of Baoshan Branch organized investigators to conduct review studies every year. Based on the investigation coverage of that year, it conducted expanded investigations on resigned and retired employees and their family members of relevant units. It organized police on many occasions in Jiangsu Province. , Zhejiang, Shanghai, Anhui and other places continue to investigate.
The Serious Case Team of the Criminal Investigation Detachment of Baoshan Branch was on a business trip. Source: Shanghai Police
Cold Case Solved: Unblocking a 23-Year-Old Murder Case
In recent years, Baoshan Police have integrated science and technology, data applications and investigation work to conduct continuous and rolling comparisons of biological samples in the system. Establish a digital "one case, one file" for paper-based case materials, innovate image technology to investigate and solve cases, analyze, correlate, and collide massive information data, continue to carry out clue verification and comparison, and continuously improve the role of accurate guidance of information research and judgment.
At the end of 2022, the Baoshan police used the latest technology to conduct laboratory analysis of the physical evidence extracted from the crime scene that year, and determined that people in Nantong, Jiangsu Province committed the crime.Based on this important clue, the Serious Case Team of the Baoshan Criminal Investigation Detachment quickly formed a 5-member investigation team and went to Nantong, Jiangsu Province to investigate. However, regrettably, the investigation team never found the suspect during more than 20 business trips spanning 14 months. people.
The criminal investigation detachment police regularly sort through the historical data of the backlog of cases. Picture source: Shanghai Police
In February 2024, the case finally ushered in a turning point. When the Jiangsu police were investigating a theft case, they found that the biological information was highly similar to the suspect in the Baoshan murder case. The Baoshan police immediately rushed to the local area. While the investigators were carrying out a large number of visits and investigations, a village cadre reported to the police after identifying the simulated portrait: This person resembled the deceased villager Shen. After comparing the household registration information, the police found that Shen's photo was very similar to the portrait. He was 36 years old at the time of the crime, and his physical characteristics were very consistent with the suspect, but he is now dead.
In order to further verify Shen’s identity, experts from the Criminal Investigation Corps of the Municipal Bureau and the Criminal Division of the Baoshan Criminal Investigation Detachment formed a technical team and confirmed that Shen’s biological information was completely consistent with the biological traces left at the scene when the crime occurred, and was exclusive. On this basis, the police combined with the electronic case files to continue to conduct interviews, verification and return visits to relatives, friends and workers who were familiar with Shen's situation.
According to the memories of Shen’s relatives and neighbors, Shen moved to Shanghai to work in decoration in 2000 and almost never returned to his hometown. In early 2002, Shen suddenly returned to the village and became cautious and cautious. He never traveled far and did not mention a word about his experience as a migrant worker in Shanghai until his death due to illness in 2015. At the same time, the police also found local workers who worked with Shen in Shanghai. According to memories, Shen had been soliciting scattered decoration work in a street garden in Baoshan City for a long time, which was consistent with the deceased's usual location.
After further scientific comparison, the suspect was the deceased Shen. At this point, the truth about the murder case that had been buried for 23 years was revealed, and the police also informed the family of the deceased and the investigators who had handled the case over the years. Although the uniform collar on the simulated portrait did not directly indicate the direction of the investigation for the police, it eventually brought the "answer" and allowed generations of investigators to return to the "original point" of the crime.
Baoshan police will give full play to the advantages of new criminal investigation tactics and new technologies and always maintain unremitting pursuit of serious violent crimes such as the backlog of homicide cases to effectively protect the safety of citizens' lives and property.
Beijing News reporter Yu Jinmin Guo Yimeng
editor Gan Hao
proofreader Li Lijun
