Fingerprints: Methods of Collecting Fingerprints

Imagine walking past your favorite park to find a crowd of people gathering around a scene where an ambulance and a few police cars are parked, plus rolls of yellow barrier tape all over the place. Your curiosity begins to befall you and you walk towards the scene, once you’ve reached the spot, you see a blood soaked lifeless body sprawled on the floor just like in the movies. You can’t help but form a series of questions in your mind, «Why was she killed?», «Who would do such a thing?», «Was there a gun?» Questions like these aren’t as easy to be answered as one would imagine, and not as hard either. Forensic science has enabled us to answer such questions via a few techniques. One of the methods is by collecting fingerprints. How exactly does one collect and analyze fingerprints?

The first step is by finding the object or surface which you suspect was touched by the criminal. This may be an object, for example a gun or a flat surface such as a table or a door. Look for slightly visible fingerprint marks on the surface and brush proper colored powder which is easily seen on the surface with a brush. For example, if the surface is black, use white colored powder. Brushing the powder will make it easier for the fingerprints to be seen.

The next step is to use a camera to take the photos of the prints. This must be done to ensure you have a backup of how the fingerprints look in case anything happens to the collected fingerprints. Once this is done, some form of tape pressed against the powdered fingerprint and placed on a 3×5 card with a contradictory color to the powder. It will then be compared manually to the collection of other fingerprints or by scanning it via a computer. This technique has been widely used for a very long time but it isn’t as effective because the print stick can be tampered with and isn’t as effective.

There are other methods of collecting fingerprints as well, such as using an electric pen and a metal filing brush, using chemical bonding agents and by using the gray scale. For example, police can use chemical bonding agents by setting the surface in a specially heated area and using superglue fumes to warm the environment thus creating a white substance on the fingerprint area. For the gray scale method, the most popular way would be livescan technology. Livescan technology compromises of a glass pad which will be used to obtain the prints are then relayed to the database.

What a way technology has carved for forensic science. Imagine a life without these technologies; murderers would get away so freely just like the murderers of the past, such as Jack the Ripper. Collecting fingerprints have certainly gone a long way!