Thursday, 8 October 2015

Fingerprint Age Determination: The Possibility Of When

No two fingerprints are ever the same even for identical twins. So, in a theft case, Peter cannot really blame Paul if his fingerprints were found at the crime scene. There will be a distinction between their fingerprints when analysed. If this is so for twins, how much distinction will it be among unrelated individuals. Imagine the wide expanse of difference that will be.

Background Knowledge
Fingerprints are simply patterns made when our fingertips touch a surface. Fatty substances and perspiration (otherwise known as fingerprint residues) are secreted by our skins which outline the contours of our fingertips so that when we touch anything, (yes...anything) the residues are left on those surfaces in whorls, arches or loops.
Try At Home Experiment
1.Get a little quantity of ink from your pen or an ink pad and a white plane sheet of paper.
2. Place a finger on the ink pad . It should be stained with ink.
3. Now with your ink stained finger on the sheet of paper, press, hold and remove your finger after 3 seconds . You can do this on different white spaces on the white sheet of paper.
4. When you remove your finger. What do you see?

Conventional fingerprinting techniques only analyse fingerprint patterns on surfaces to determine the identity of the individuals. But no technique has yet been developed to determine how long a fingerprint has been on a particular surface (at least not for now).
For instance, consider the doorknob of the female convenience or restroom of a popular restaurant. If the dead body of a young female was found on the floor of the restroom, it becomes a crime scene. Many women must have used the doorknob to enter the restroom. The door knob will most likely contain multiple fingerprints starting from the current day to several months before. Investigators can easily develop the fingerprints found on the doorknob but will find it impossible to determine the new ones from the old which could help to identify possible suspects present  at the time of the murder.

Good News
A recent research showed that this could be possible...(in the near future though). The studies revealed that there was movement of fingerprints residues over an area from their original position under a period of time. The original fingerprint becomes blurred over time. Imagine a small cube of ice on a flat plate. You don't expect it to remain the same after 20 you? It will definitely melt and spread. That is what happens to a fingerprint after a period of time.

This research has demonstrated that developing such a technique is not impossible. Fingerprint analysis as a forensic tool has been used  severally by crime investigators  around the world to link suspects to crime scenes. It will be a major breakthrough in the world of forensic science when a technique that can determine how long a fingerprint has been on a surface was developed.

This technique can help investigators to identify individuals who were present around the time a crime was committed.