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Intriguing Facts About The History Of Fingerprint Forensics

People have been studying the unique characteristics and properties of fingerprints for thousands of years. In ancient Babylon, for example, clay impressions of fingerprints were used to seal business deals. Sir William Herschel is recognized as one of the first Europeans to begin collecting and studying fingerprints in the 1850s, which inspired others to do so as well.

However, fingerprint analysis didn't become common in crime-solving forensic science until the early 20th century. Here are some facts and tidbits about fingerprint forensics and how they came to be.

  • A Fingerprint Can Reveal Your Gender

    Dr. Jan Halamek, a professor at the University of Albany in New York, led a research team that came up with a test to determine a person's gender based on their fingerprints. Instead of examining size and shape, Halamek's test examines and analyzes the amino acid compounds in latent prints.

    These fingerprints are created by sweat and natural oils, so heating the prints and applying a special chemical dye causes them to turn a specific color based on the concentration of amino acids left behind by the skin. Due to the fact females have more amino acids than males, Halamek claims the test is 99% effective.

  • A Commonly Used Fingerprint System Was Created By A Eugenicist

    A Commonly Used Fingerprint System Was Created By A Eugenicist
    Photo: William James Herschel / Wikimedia Commons / Public Domain

    Sir Francis Galton, the man who may have coined the term "eugenics," is regarded as something of a fingerprint pioneer. An anthropologist and the cousin of biologist Charles Darwin, Galton was interested in the controversial idea that humans could be selectively bred to achieve desired traits. He theorized a person's fingerprints might be able to identify their racial characteristics or level of intelligence.

    Galton's study of fingerprints led him to create a classification system called Galton's Details. The system identifies the raised ridges in a print based on five characteristics: the enclosure, the short ridge, the dot, the ridge ending, and the bifurcation. Modern-day investigators still study these details to determine whether or not two prints are alike.

  • The Pores In A Fingerprint Are Just As Important As The Ridges

    The Pores In A Fingerprint Are Just As Important As The Ridges
    Photo: Unknown / Wikimedia Commons / Public Domain

    French criminologist Edmond Locard began studying fingerprints back in 1910. Locard's specialty was poroscopy, which examined not only the ridges of a fingerprint but also the marks left behind by the pores in the skin. Several years later, Locard determined that if 12 points on two fingerprints match each other, then those prints are made by the same finger.

    This standard is often still used to this day. However, a given country's legal system sets different standards for the number of matching points required to conclusively connect two fingerprints.

  • Fingerprint Evidence Comes In Three Different Types

    People leave behind three different types of fingerprints that crime scene investigators look for: patent, latent, and plastic. Patent prints are easily visible and left by substances like blood, ink, dirt, and grease. If someone with a bloody hand touches a solid surface and leaves behind a print, that's a patent print. Latent prints aren't visible at all; they're made of the sweat and oils present on a person's hand. People leave latent prints behind all day long and never even think about it. These are the types of prints that are lifted at crime scenes using special powders and brushes.

    In contrast, plastic prints are three-dimensional. These prints are made in paint, tar, soap, wax, and even clay. When law enforcement or crime scene techs process a crime scene and see patent or plastic prints, they simply take a picture of them, as they do not need to be processed in the same way as latent prints.