He has the answers in his hands…

Fingerprint detail on male finger.

Image via Wikipedia

Many people do not realise what evidence you can get from friction ridge details on hands and as such I decided to compile a short guide to chemical processes.

I will not tell you how to carry out those processes here because a lot can be dangerous and to produce the evidence in court you would need to be certified and suitably qualified.

The first thing you do need is a working knowledge of fingerprints and the minute that make up the ridges.

As you can see there are many areas of the fingerprint that are important and everyone has different ones.

No two fingers are ever the same meaning the results of a fingerprint match are conclusive.

But it’s not only the fingerprints that contain ridges, other areas of the body carry them as well.  The palms for instance and very valuable in the hunt for criminals, that’s why  it is very important for the Police to maintain an active database of not only fingerprints, but palm prints as well.

Many countries are now taking palm prints every time they take fingerprints due to the ability of their comparison experts to identify a very very small area of ridge detail.

As you can guess, none of this is like the TV shows, CSI: MIAMI or CSI: New York. they are dramatic and nothing like real life. Although they do use a number of the products real life investigators use but the timings are completely shot to bits.

As is the fact that a Crime Scene Technician is able to be first on the scene, gun totting, and blues and twos everywhere. If only!!!

Once you have found a piece of evidence you will need to decide what processes you are going to carry out on it.

Now there are destructive and non destructive processes and you must always carry out the non destructive processes first. These can be completed using powders, chemicals or other processes involving equipment such as the ESDA from Foster & Freemen Ltd in the UK.

Once you have decided what processes you are going to use, ensure you have photographed your evidence. I recently worked in an organisation where the boss said NOT to photograph all the items before processing. Unfortunately if you are working on evidence that has specific markings like a letter or receipt, that can be obliterated during the processing.

YOU MUST ensure the evidence is photographed prior to processing. This can also be used to indicate to the court what state the evidence was in when it reached the lab.

Of curse should the unimaginable happen and that piece of evidence was ever lost, you also have a record of what it was. Not best evidence no, but its a record.

Following your photography and subsequent searches with light sources and chemicals the evidence can be packaged and sent back to the investigating officer ready for his court dates.

It should not be disposed of even if it’s a vehicle or large item. If the item will spoil (like and apple for instance) then it should always be disposed off after photography.

After you have used your chemicals to recover your marks you then need to capture them and enter them onto the Automated Fingerprint Identification System (AFIS) which is housed in most Criminal Record Offices.

From there it can be searched against either a specific person who is held on file, a person who has supplied prints for that enquiry or against the database for a speculative search.

Should any of these be positive the check must be verified by a number of people before it is published and the person arrested.

Most of the time that is all there is to it but occasionally the experts don’t agree and outside verification must be sort.

If you need outside verification one company you can use is this one Complete Policing, Defence and Medical Solutions Ltd who are based in Trinidad & Tobago.

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