Fingerprint Investigation

The human skin is composed of three parts: the epidermis and the subcutaneous tissue. Fingerprints are the raised lines on the epidermis, and the starting points, end points, forks, and combinations of these raised lines are known as detail features. These detail features have an infinite number of arrangements, making each person's fingerprint, and even each line within a fingerprint, unique. Despite the billions of people in the world, no two fingerprints have been found to be exactly the same, even among identical twins. Fingerprints begin to form in the third or fourth month of fetal development, and by around six months, they are fully formed. As infants grow, their fingerprints simply enlarge and thicken, but the patterns do not change. In other words, once our fingerprints are formed, they remain unchanged for life.

Fingerprints are like a person's 'identity card'. Fingerprint forensic investigation is to identify the fingerprint patterns of the suspect's fingers to help investigators determine whether this person has the possibility of being a real criminal. So, who was the first person to think of this good idea? According to archaeological discoveries and records in historical books, our country began to use fingerprints left by criminals at crime scenes to solve cases more than 2500 years ago in the late Warring States period.

In 1975, a batch of bamboo slips from the Warring States period of the Qin State were excavated from Yunmeng in Hubei Province, which is known as the "Yunmeng Bamboo Slips". The date of the "Yunmeng Bamboo Slips" is approximately between 251 and 221 BC, which is during the late Warring States period before the unification of China by Qin Shi Huang, the first emperor of China.

The 'Yunmeng Bamboo Slips' contain the 'Feng Zhen Style · Xue Dao' slip, which vividly records a case of a criminal digging a hole to enter a household to commit theft. The bamboo slips specifically emphasize that the criminal's 'knees and hand prints, knees and hands each six times' were left on the hole walls of the crime scene. This historical record indicates that by the late Warring States period, our ancestors had already considered 'hand prints,' which we today call fingerprints, as an important part of crime scene investigation, and used them as important evidence in solving crimes and identifying the culprit. After the Qin Dynasty, cases of using fingerprints to solve crimes were common in our historical records. By the Tang Dynasty, fingerprints were applied to documents; and in the Song Dynasty, hand prints became official evidence in criminal proceedings.

The history of fingerprinting for crime solving originated in Western Europe. British morphologist Nathaniel Hartsoeker described various fingerprint shapes in the Philosophical Transactions in 1684. It wasn't until the early 19th century that German Professor Albrecht von Haller classified fingerprints into nine categories. In 1858, the British Governor-General in India, William Herschel, had the idea of requiring natives to leave their fingerprints when signing agreements. In 1877, he also required criminals to leave their fingerprints before being incarcerated. Coincidentally, at the same time as Herschel, Henry Faulds, who was a surgeon at the Tokyo Hospital, turned his attention to the fingerprints found on the old gatehouse excavated in Edo.

On October 28, 1880, Forensics published a letter in the British scientific journal "Nature", discussing "when bloodstained fingerprints leave traces on things like soil or cups, they can lead to the identification of criminals using scientific methods". British scientist Francis Galton pioneered the fingerprint classification coding technology based on the work of previous researchers, and published a book on fingerprints in 1982. Among them are three significant conclusions: fingerprints remain unchanged throughout life; fingerprints can be identified; fingerprints can be classified. Subsequently, J. Busselatchie, inspired by Galton's research, created a practical fingerprint classification method in 1892. He detailed the superiority of fingerprinting in his book "Introduction to the Use of Anthropometry and Fingerprinting". In 1896, the Argentine Police Department became the first in the world to use fingerprinting, and eventually the police used fingerprints to prosecute criminals. This marks the beginning of fingerprinting for criminal investigation.

Modern high-tech has given the ancient forensic technique of fingerprint identification a powerful boost, with the introduction of automatic fingerprint recognition systems enhancing the technological content of crime solving. Nowadays, in many cities across our country, there are forensics fingerprint databases operated and managed by computers, as well as databases for fingerprints at the crime scenes, which have significantly improved the speed and accuracy of crime solving. Anyone with a criminal record who commits another crime can be easily identified by the police if they find a fingerprint left at the scene. This process can be completed in just a few minutes with the help of the automatic fingerprint recognition system.

The human skin is composed of three parts: the epidermis and the subcutaneous tissue. Fingerprints are the raised lines on the epidermis. Due to human genetic characteristics, although everyone has fingerprints, they are all unique. By extending your hand and observing carefully, you can discover that fingerprints are divided into several types: there are concentric or spiral lines, which look like water vortices, called whorl patterns; some lines are open on one side, like a sieve, called loom patterns; some patterns look like bows, called bow lines. In addition to the shape of the fingerprints, the number and length of the patterns are also different. It is said that no two people have been found to have exactly the same fingerprints. Fingerprints begin to form in the third or fourth month of fetal development, and they are formed around six months. As an infant grows into an adult, the fingerprints only become larger and thicker, but their patterns remain the same.