You’ve Been Printed!
When William Herschel discovered fingerprinting to keep people from stealing pensioners’ cash, he never would’ve thought it would translate into one of the most important facets of forensic science today (McDermid 117 ). Edmond Locard, a pioneer of forensic science,
once said, “Every contact leaves a trace” (McDermid 116 ). In other words, every contact someone makes leaves some form of mark on the surface. This was laid down as one of the quintessential principles in the field of forensic sciences. For instance, one of the major groups of forensic science is fingerprinting, which is the act of taking an impression of a finger. This essay will inform about fingerprint biology, taking and matching fingerprints, the application of fingerprints today, and, ultimately, why fingerprinting is a backbone of the forensic science discipline.
As unnoticeable as they seem, fingerprints have a very detailed biology. Fingerprinting is based on visible ridges, or dark lines found on fingerprints (“Fingerprint Recognition” ). These ridges vary in shape from finger to finger, as no two fingerprints are the same. The three basic shapes of fingerprints found are loops, arches, and whorls. First, loops are a type of fingerprint that bend over themselves to form a U-like shape (Platt 47 ). These loops form and end on the same side of the finger, unlike arches and whorls (See Appendix 1, Figure 1). Next, arches are a second type of fingerprint that are layers of ridges that stack up on each other, eventually forming an arch-like shape (See Appendix 1, Figure 2) (Platt 47 ). Finally, whorls are the third basic fingerprint shape. This shape forms rings around a central point (See Appendix 1, Figure 3). Not only is this the only type of fingerprint that is given a point value when printed, it is also the most commonly found type of fingerprint (Platt 47 ). These point value systems were built on the foundation of matching minutiae, a pair of ridge’s position and direction (“Fingerprint Recognition” ). Minutiae are certain ridge characteristics which give every single fingerprint its uniqueness compared to one another. Consequently, the ridges and minutiae of a finger, fingerprinting has individuality, making it a founding element of forensic science.
Edward Henry, a police chief in Bengal, India, was one of the founding fathers of fingerprinting. Henry created the “Henry Classification System,” where the physical characteristics of a fingerprint created a unique assigned number. Following that, they could be sorted into 1,024 unique pigeonholes, or codes (McDermid 120-121 ). For instance, a right thumb with a whorl would be set into a different pigeonhole compared to a left index finger with an arch. As a result, the Henry Classification System would last for years upon end and inspire the AFIS (Automated Fingerprint Identification System) that is currently in use today. Few methods of other fields of forensic science have lasted as long as fingerprinting has.
There are a variety of ways a fingerprint can be taken and matched. In the past, ink-and-paper methods have been common, but with the rise of new technology, many fingerprints can be tracked digitally. The new way fingers are printed is all thanks to live-scan sensors. The use of these has made the process of taking fingerprints surprisingly simple. Before the fingerprint is recorded, making sure the fingerprint is clean is important, as substances, such as oil and dirt, can throw off an accurate fingerprint (“Recording” ). Once a clean fingerprint is placed over the live-scan sensor, the ridges are scanned, and a basic image, or query print, is formed (Jain 38 ). From this query print, minutiae points are extracted and compared with other models that have come from the database the fingerprint is being used in (Jain 38 ). These prints are compared to each other in an attempt to match at least two alike minutiae points. If all minutiae match up, then the two fingerprints have came from the same person. Normally, though, matching anywhere from eight to twelve different minutiae on a similar finger is a good sign they could be from the same person (Jain 39 ). Now, this is challenging due to variability, so the two models are aligned during the comparison (Jain 38 ). These databases also contain the name of those who have been previously printed in case someone pretends to be another person, which is known as multiple enrollment (Jain 37 ). This seemingly quick scan is all it takes to take and match a fingerprint, which, with the addition of technology, has widened the uses of fingerprints.
Of course, there are some abnormalities whilst taking a fingerprint that need to be noted. If the person’s finger is missing or fully amputated, a notation may be made (“Recording” ). A notation is key in order to have all the data necessary for someone to review these prints. With deformed fingers, worn fingerprints, and scarred fingers, the best effort will be made to record impressions (“Recording” ). If unable to take impressions, a notation can be made. Do not record any extra fingers a person may have (“Recording” ). They are not necessary for fingerprinting, nor will they provide any extra information. These tiny exceptions can make big differences, since fingerprints can distinguish us differently from every other person in the world.
With the rise of biometric technology, use of fingerprints in technology and security are popping up all over the place. One main use of fingerprint recognition is using prints to access buildings, rather than a key card or passcode (Thakkar ). The use of fingerprints in buildings is faster and more reliable than passwords and key cards since we can’t lose our fingerprints, though they can be worn down. It is also very secure, with password security continuing to be strengthened (Rehmeyer ). This process would be done with live-scan sensors, with a database of all the workers’ fingerprints (Thakkar ). Not only would this verify, or make sure the person is who they say they are, but it would also track office hours of employees (Thakkar ). As a result, the combination of technology and fingerprinting, can make identifiable tasks more easily accomplished while providing better security.
The use of fingerprint application is also very common in the banking and finance industry. As one of our best identifiers, fingerprints are very secure. Banks can use fingerprint swipes to link a fingerprint swipe to an account (Thakkar ). However, there are situations where they may not be as secure as we hope, as fingerprint security is not perfect. There is a one in fifty-thousand chance our fingerprint will randomly match with another person’s when using Apple ID (“Fingerprint Security” ). These flaws in security are rare, but as the increase of biometric payment increases, such as Apple Pay, which uses Apple ID, little mistakes can lead to big breaches. For instance, Global Payments, a data processor for four major credit card companies, was breached in 2012, with over 1.5 million credit card numbers (“Fingerprint Security” ). The problem with this is that payment companies aren’t keeping the software on their systems to the highest standard, resulting in problems like this. This is just one example of fingerprint-based systems that are growing in usage because technology is finally able to recognize the uniqueness of the individual fingerprint.
In conclusion, fingerprints have a complex biology, a simple way of taking and matching them, and many useful applications in all job fields. The ridges on fingerprints allow for complete idiosyncrasy between everyone else in the whole world, making them a great identifier. They also have a variety of ways to physically and digitally track traces of someone. Fingerprints, no matter how miniscule they seem, can improve entrance security by leaps and bounds through verification, and continue to be a good resource to society and a pillar of forensic science. Fingerprinting has come a long way, from Herschel to the AFIS. Pretty soon, being anonymous will be a thing of the past.