The content of this article is based on authoritative historical data, and there are citations at the end of the article.
One morning in 1991, a young female teacher, Wei Shumin, and her 4-year-old son rode their bicycles to the market as usual, but never returned home.
Their bodies were found in an abandoned machine well at the entrance of the village, and how many unsolved mysteries are hidden behind this tragedy?
The local police department launched an investigation immediately after the incident, but due to technical limitations at the time, the murderer could not be found. The clues of the case gradually fell silent under the dust of the documents.
But is the truth really buried there?
One day in May 1991, the sun was shining and the country air was filled with the smell of fresh earth and spring flowers.
On this day, Wei Shumin, a female teacher in the local village, was ready to take her 4-year-old child to the nearby market to buy daily necessities as usual.
Her bike drove slowly along familiar country roads, lined with glowing green wheat fields and occasional visible fruit trees. The child sits in the child seat in front of him and observes the surroundings curiously along the way.
On that day, the market was particularly lively, and the villagers greeted each other and exchanged information about the growth of their crops and their crops. Wei Shumin stopped the car, locked it, and then took the child to pick vegetables and fruits.
She bought fresh beans and tomatoes, as well as sweet oranges that the kids loved. In the trading room, she talked to other villagers and asked about the children's growth and learning, and everything seemed to be so calm and harmonious.
Just as she was about to go home, dark clouds gathered on the horizon and the wind gradually increased. She hurriedly took her children on her bicycle and wanted to get home before the rain came. Unfortunately, they did not return home.
The next day, when the villagers noticed that Wei Shumin's mother and son had not returned, they began to search around the village. Eventually, in an abandoned machine well at the entrance of the village, the bodies of her and her children were found.
After receiving reports from villagers that the bodies of Wei Shumin and her son had been found, the local police department immediately activated an emergency response mechanism.
The police chief personally commanded and ordered all mobilized forensic resources in the county to be assembled immediately and prepare to go to the scene of the crime for an emergency autopsy.
Due to the extremely serious nature of the case, and also considering the protection of the scene, the operation was chosen to be carried out under the cover of night to avoid onlookers and disturbances that may be brought during the day.
In the darkness of the night, a team of well-equipped forensic doctors and police arrived at the scene of the crime. They first cordoned off the scene and set up a cordon to ensure that unrelated people were not allowed to approach.
The forensic team, armed with portable lights and the necessary forensic equipment, began the initial examination of the body.
Under the illumination of the lights, the medical examiner noticed that the bodies of Wei Shumin and her son showed obvious signs of violence. Wei Shumin's head was hit multiple with heavy blows, and her skull showed depression, which was direct evidence of fatal injuries.
Her clothing was partially torn, indicating that she had been subjected to extreme violence before being killed. Her child also showed signs of a heavy blow to the head and other injuries on his body, consistent with injuries caused by heavy objects or falling from heights.
While the forensic team was conducting the autopsy, police investigators conducted a careful survey of the surrounding environment. There are obvious traces of drag on the ground in the well room, indicating that the murderer had dragged the two bodies to the well after killing the mother and son.
Some sundries in the machine shaft room were disrupted, and some daily necessities were discarded at will, showing the chaos at the scene at the time of the crime.
Upon further investigation, the police found a number of items left behind in the shaft room that may have belonged to the murderer, including some broken fabrics and remnants of ropes that may have been used for tying. The physical evidence was carefully collected and prepared to be sent to the laboratory for detailed analysis.
Subsequently, the forensic team collected various samples from Wei Shumin and her offspring, including blood, tissue, and possibly exogenous substances, for subsequent forensic analysis and toxicological testing.
In 1991, forensic science and DNA technology were not as advanced as they are today, and many modern forensic methods were still in their infancy. This poses a great challenge for forensic doctor Fan Xinhe and his team.
In the case of Wei Shumin and her son, although the forensic team was able to extract some key biological samples from the body, such as sperm spots, they were unable to use these samples for precise DNA analysis to determine the identity of the killer due to technical limitations at the time.
After the incident, Fan Xinhe and his team collected a variety of samples in the machine well room and on the body. This includes bloodstains, hair, and other residues that may be associated with the crime.
All of these samples have been carefully labeled and preserved, in the hope that one day a technological breakthrough will help unlock the secrets behind this evidence.
In the early 90s, DNA identification technology was mainly limited to very limited applications, such as determining paternity, and the error rate was relatively high, and it was far from widespread in forensic analysis.
In addition, the technology of the time was mainly capable of analyzing very large DNA samples, while DNA extracted from crime scenes was often in small amounts, making it difficult to analyze accurately.
Fan Xinhe and his team tried their best to use the scientific and technological means available at the time to conduct the investigation. They sent samples collected from the scene to provincial laboratories in the hope of narrowing down the suspects by comparing blood types and other viable biomarkers.
However, due to technical limitations, these efforts have not yielded decisive results. Although blood grouping helped them rule out some unrelated people, it was not very helpful in identifying the killers.
As the investigation progressed, Fan Xinhe and his team also tried other methods, such as reconstructing the scene of the crime scene, inferring the crime process through the analysis of the ground and surrounding environment, and drawing a portrait of the suspect through the description of eyewitnesses.
They also work with other police departments to check records of similar cases, hoping to find potential connections or patterns.
Unfortunately, despite tremendous efforts, the investigation has been slow due to inadequate key DNA analysis techniques, and for many years it has not been possible to find conclusive evidence to locate the killer.
The case gradually became an unsolved mystery, hanging on the hearts of Fan Xinhe and his team, and became a stumbling block in their careers.
In 2016, the development of science and technology, especially the significant progress of DNA identification technology, has provided new ways to solve many unsolved cases.
This technological advancement allows forensic experts to extract DNA from extremely small samples and make highly accurate matches. This is an important turning point for the investigation team in the case of Wei Shumin and her sub-case.
In this year, the case team decided to re-examine the physical evidence that had been kept in the case for many years. On the orders of the local police department, biological samples collected from the scene of the crime in the early years were sent to modern laboratories for in-depth analysis.
Including samples of sperm stains from Wei Shumin and her children, although these samples have been preserved for many years, the DNA can still be used for analysis thanks to the professional preservation technology of the forensic team at the time.
The lab performed a comprehensive analysis of these DNA samples using next-generation sequencing technology and a multi-locus matching system. The results showed that a unique set of DNA sequences was obtained from the sperm samples taken from Wei Shumin's corpse.
The team then used the results to match the records in the national DNA database with the expectation of finding individuals who matched the DNA.
After accurate data comparison, the case handling team locked down a man surnamed Shi who was highly consistent with the DNA of the crime scene, this man's name was Shi, a 75-year-old man. His DNA is highly consistent with samples from the crime scene.
The case team conducted an in-depth investigation of Shi's background and found that his life history and past criminal records matched the description of the suspect in the case in many ways.
He has been documented by the police for multiple violent incidents and has a long criminal background.
Subsequently, the police followed and investigated Shi to collect more evidence related to the case. After ensuring that there was sufficient evidence, the police took action and went to Shi's residence to conduct a search.
At Shi's home, the police found some items that may be relevant to the case, including old clothes and some personal belongings, which were sent to the laboratory for further DNA and other relevant analysis.
After DNA technology confirmed that Shi had a very high match with the sperm spots left at the scene of the crime, the case handling team began to investigate Shi's background and history more deeply.
In the course of the investigation, they found that Shi had a son, Shi Jiazhou, who had died of illness ten years ago.
Although the preliminary DNA test results linked Shi to the case, the case team needed further evidence to identify exactly who the actual perpetrator was.
Due to Shi's age, and he was already old at the time of the case, the case handling team speculated that his son Shi Jiazhou may have a more direct connection with the case.
So, they decided to conduct an open coffin autopsy on the late Shi Jia Zhou to obtain his DNA samples for comparison.
After this decision was issued, Shi strongly opposed it. Not only is he concerned about the financial burden of having to be reburied after an open coffin autopsy, but he may also be uncomfortable with an open coffin autopsy due to cultural and traditional factors.
Considering the seriousness of the case and the urgent need to resolve the case, Deputy Director Fan Xinhe insisted on DNA extraction of Shi Jiazhou's body.
After some legal process and ethical considerations, the court granted the application for an open coffin for an autopsy.
The open coffin autopsy is carried out under the supervision of professionals. In a tight environment, the forensic team carefully opened Shi Jiazhou's coffin.
Although Shi Jiazhou's body has been buried for many years, with the help of modern forensic technology, experts are able to extract samples from the bones that can be used for DNA analysis.
The extracted DNA samples were sent to the laboratory for detailed analysis and comparison. The results showed that the DNA extracted from Shi Jiazhou's body was in good agreement with the DNA of the sperm spot at the scene of the crime.
This discovery almost confirms that Shi Jiazhou carried out a fatal attack on Wei Shumin and his son at the time of the crime, which ultimately led to their deaths.
LI Xiqi,LI Shouyi. Rural World,2001,0(1):8-9