July 26, 2023
Footwear impressions can provide valuable insights to a shoeprint expert. They can “speak”, revealing information about the individuals who left them, including their height, age, walking posture, and overall posture. Further more, these impressions offer crucial clues that can assist in the investigation work.
In February 2021, a devastating incident took place, resulting in the death of a 93-year-old man who resided alone in a nursing home. The crime scene yielded 15 shoeprints, which played a significant role in the subsequent investigation.
Police officer Cui, a shoeprint expert, was called to the crime scene to investigate the footwear impressions left behind. Based on years of experience in shoeprint identification, officer Cui confirmed that the shoeprints were left by seven pairs of shoes. After analyzing the movement patterns of the perpetrators who left the shoeprints in the house and investigating those who were closely related to the elderly victim, six people and 14 shoeprints were excluded. Only one shoeprint with partial patterns remained, which could potentially belong to the suspect. Using technology recognize shoeprint characteristics, officer Cui discovered that it was left by slippers. This discovery narrowed the investigation, suggesting that the suspect was likely someone in the nursing home. Officer Cui, who has worked in the field of shoeprint identification for decades, identified key factors such as the degree of wear and tear of the slippers and the size of the marks, and speculated that the suspect was approximately 45-50 years old, 162-167 cm tall,and thin.
Based on the important clues provided by officer Cui, investigators began to investigate all staff and elderly people in the nursing home who met the suspect's description. Two hours later, the suspect was found wearing shoes that matched the shoeprints left at the scene. After a quick interrogation, the suspect confessed to the crime, and the case was successfully solved. The suspect was identified as a 49-year-old woman who was 165 cm tall and thin.
Early one morning in June 2014, the police command center of a County Public Security Bureau received a report of a body found in a small pond. Upon receiving the alarm, the police promptly arrived at the crime scene to conduct an investigation. They discovered the lifeless body of a naked woman in the water.After examining the body, it was determined that the woman had been raped, murdered,and then disposed of in the small pond. At the crime scene, the police found one of the victim's hair clips and several suspicious shoeprints around the perimeter, but no other evidence. Further investigation in the surrounding villages confirmed that the deceased was the daughter of a local farmer Wang.
To gather clues from the shoeprints, the County Public Security Bureau invited shoeprint identification experts. These experts analyzed the suspicious shoeprints left at the crime scene, as shoeprints left by the same person can provide valuable evidence. By examining factorssuch as size, length, pressure distribution, and gait analysis of multiple shoeprints, shoeprint identification expert Guo determined that the suspect's height ranged between 1.75 and 1.82 meters, and estimated their age to be around 30 years old. Additionally, the experts provided a description of the suspect's body. Based on this information, the police launched an extensive investigation into potential suspects, but were unable to locate the perpetrator.
In early July 2014, a significant break through happened in this case. A victim in a recent rape case, identified as Jiang, described the suspect's modus operandi and posture, which closely resembled those of the suspects in the previous case. The police obtained the suspect's phone number from Jiang and were able to confirm that the suspect's name was Li. Li was subsequently arrested 15 days later. Overall, the collaboration with shoeprint identification experts played the crucial role in advancing the investigation and ultimately leadingto the arrest of the suspect.
After identifying the victim, the suspect admitted his responsibility for the rape but firmly denied any involvement in the rape and murder case that occurred in June. In order to gather more evidence, the Public Security Bureau invited expert Guo the second time. Guo conducted a simulation and analysis of the shoeprints and barefoot footprints left by the suspect, Li,and arrived at a surprising conclusion.
Accordingto Guo, based on the plantar pressure distribution of the shoeprint at the crime scene, the pressure distribution during movement shown by the simulated shoeprint test of the suspect, and the movement track of the shoeprint, it can be confirmed that although the suspect wore different shoes in the simulation experiment and the two cases, the foot structure, body characteristics, and height characteristics displayed by the shoeprint are consistent. Therefore, it can be concluded that the suspect, Li, bears a strong resemblance to the perpetrator of the June case. Building on the expert's identification, the task force police conducted several interrogations of Li. Finally, in the early morning of July 29, the suspect Li confessed to the rape and murder of Wang’s daughter.
Since 1993, there have been rulers made for estimating a person's height and age based on shoeprints. This incentive not only received a national patent but also earned the prestigious "Excellent Thesis Medal" in Germany. As of 2020, over 120,000 rulershad been sold in China.