Fingerprints

This is day six of the A to Z Challenge. Wow, this first week has flown by in a blur.

English: Picture of an arch fingerprint pattern. Image source: NIST. Category:Fingerprints (Photo credit: Wikipedia)

When it came to an F post I decided to go with another forensic technique. The good, old-fashioned FINGERPRINT.

Yay!

• Fingerprints are formed about 28 weeks after conception. These ridges stay with us for the rest of our lives, even surviving for some time after death. A useful tool in post-mortem identification;
• No two fingerprints are identical.

From 1901, England and Wales (along with a host of English-speaking countries) adopted the fingerprint classification system developed by Sir Edward Richard Henry in the Metropolitan Police Fingerprint Bureau. Well over a century of analysis later and the fingerprint still plays an important role in evidence gathering from the scene of a crime.

In your crime writing the good old fingerprint shouldn’t be underestimated. As I mentioned in my DNA post and Blood Analysis, the newer techniques are ground breaking, but people still leave prints. Be they, finger, palm or other prints such as an ear pressed against a window. All can be used by your Crime Scene Investigator or lead detective.

Prints fall under three main categories:

• Loops – account for around 60 per cent of patterns;
• Whorls – 35 per cent; and
• Arches – account for the remaining 5 per cent.

Each of these three categories are broken down further and there is a whole host of variations in patterns: Radial and Ulnar Loops; Plain and Tented Arches; Central Pocket and Double-Loop Whorls amongst others. You can see why no two prints will be the same.

We’ve gone from ink and the ten-card of prints to digital scanning. And, over a century after they were widely introduced, you can now buy junior forensics kits for children including fingerprint analysis. Start ’em early 🙂

In your crime fiction you could use one of the three types of prints.

• Latent prints cannot be seen with the naked eye, but developed during the forensic development of your surface;
• Visible prints, has your killer left a bloodied print or even the old man stealing your main protagonist’s car could have left a greasy print on the garage door;
• Plastic prints are like negatives. Soft surfaces such as clay receive the impression of the print.

Many, many options to track your villain down.

Happy crime writing.

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This is my F post for the A to Z Blogging Challenge. A list of all my A to Z Blogging Challenge posts are to be found here.

My pictures today are from the Filey on the east coast of England. A lovely beach to sit back and enjoy the sea view!