Exposed :: Fingerprints

There are 8 main types of fingerprints. They are...

Radial Loop

Ulnar Loop

Plain Whorl

Plain Arch

Tented Arch

Central Pocket Loop

Accidental Whorl

Double Loop Whorl

Exposed :: The History of Fingerprinting

Although fingerprinting has gotten really technical within the last century, it has been used for hundreds of years in it's simplest form.

The first discovery of the existence of fingerprinting was when an ancient picture-drawing of a hand with ridge shaped patterns were discovered on a hand in a cave wall in Nova Scotia, Canada. In ancient babylon, fingerprints were used as signatures are used today, as proof of business transactions. Thumbprints were also found in ancient China on clay seals. In 14th century persia, many official government papers were impressed with fingerprints. A doctor used these papers to conclude that no two fingerprints were alike.

In 1686, an Italian professor at the University of Bologna named Marcello Malpighia, who was a professor of anatomy, noted that their were different loops, swirls, and ridges in fingerprints. Although he made no note as to if these markings could be used to identify different prints, but it was still a breakthrough in fingerprinting history. A layer of skin was named after him, the Malpighi layer.

In 1823, John Evangelist Purkinje, a professor of anatomy at the University of Breslau, published his theorem about the 9 fingerprint patterns. He also didn't mention how fingerprints could be used to identify a person.

The first trace of fingerprinting in English culture was by William Heschel, a Chief Magistrate in Jungipoor, India. He used finger and handprints as signatures to contracts with native businessmen.

In 1880, Dr. Henry Faulds is credited to being the first person to identify a fingerprint after he found a greasy print on an alchohol bottle.

Juan Vucetich made the first fingerprint identification of a criminal in 1892. He identified Francis Rojas, a lady who murdered her two sons and then cut her own throat to make it look like someone else did it. Her bloody fingerprint was left on a door, and it led Vucetich into discovering she commited the crime.

In 1903, New York State Prison started the first system of booking criminal's fingerprints. More and more prisons soon followed.

In 1924, the FBI started booking fingerprints regularly, as the Congress established the Identification Division of the FBI. By 1946, the FBI had made over 100 million fingerprint cards in manually maintaned files. By 1971, they had 200 million cards.

Most agencies now use Automated Fingerprint Identification Systems (AIFS).

Exposed :: Types of Fingerprints

On the above post, you can see the different fingerprint patterns and their names. But when I say "types" of fingerprints, I mean the actual visible spectrum of the fingerprints at a crime scene. There are three different types of fingerprints, latent, patent, and plastic.

Latent: Latent fingerprints are the hardest to see and find on the crime scene. The word latent means hidden or invisible. The latent prints are usually created when sweat covers an area of the body, whether a fingertip, hand, foot, etc, and the sweaty area brushes a surface such as a table or a wall. Latent fingerprints will usually be lifted and brought back to the lab or headquarters for further investigation.

Patent: Patent fingerprints are usually considered the easiest to see and find on the crime scene. Patent fingerprints are usually created when substances such as dirt, paint, blood, and so on are present on an area of the body. When that area, whether a hand, fingertip, foot, etc, brushes or even touches a surface such as a table, wall, floor, or counter, it will leave some sort of mark that should be easy to identify. Instead of lifting the print as they would with latent fingerprints, they would usually just take a picture of it and bring it back to headquarters for identification.

Plastic: A plastic print is a print left on an imprintable substance such as wax, putty, and grease. They aren't too hard to see once it's there in front of you, but finding them would probably take some time. The substance that the plastic print was left on would be taken back to the lab or headquarters to be further investigated.

Exposed :: Lifting the Prints

When lifting fingerprints, different approaches are taken for different types of fingerprints. For these two specific lifting techniques, I will list the steps needed to be taken to lift latent fingerprints off of different surfaces.

Solid Dark Colored Surface:

STEP 1: Find a good print.

STEP 2: Use a white powder, such as talc, and gently cover the entire fingerprint with it.

STEP 3: Lightly blow off the excess powder. There should now be a visible print.

STEP 4: Using a clear piece of tape, cover the entire area to transfer the print off of the surface.

STEP 5: In this case, you can place the strip of tape onto a black sheet of paper. The print should now be easily visible and ready for the identification process.

Solid Light Colored Surfaces (Including Glass):

STEP 1: Find a good print.

STEP 2: Use a dark powder, such as graphite, and gently cover the entire fingerprint with it.

STEP 3: Lightly blow off the excess powder. There should now be a visible print.

STEP 4: Using a clear piece of tape, cover the entire area to transfer the print off of the surface.

STEP 5: In this case, you can place the strip of tape onto a white sheet of paper. The print should now be easily visible and ready for the identification process.

Uncovered :: History of Handwriting

As fingerprinting does, handwriting has a long history. Over 2,000 years ago, Aristotle noticed a correlation between a person's handwriting and their personality. The first book on handwriting analysis was published in 1622 by University of Bologna professor Dr. Camillo Baldo. His book, titled "A Way of Knowing the Nature and Qualities of a Writer from a Letter Written", explained that if you were to learn enough about handwriting analysis, you could be able to tell the thoughts and emotions more in depth than the actual words he is writing.

An Ohio man named Bruce Steiner scored big at a Cleveland flea market when he bought what was supposed to be Abraham Lincoln's final signature. Supposedly, this was a real signature of Lincoln the day he was assassinated. Because many thought it was a fake, Steiner was able to buy it for $20. But after a handwriting analysis, it was proved as Lincoln's actual signature. Imagine how much that could be worth today.

The first time handwriting analysis was used for a crime investigation in America was when young Charles Lindbergh Jr. was kidnapped from his home in 1932. Twelve ransom notes were received between March 1st and April 2nd that year, all coming indirectly from the kidnapper Although the 20 month old baby was soon found dead, the investigation carried on for 2 years. Eventually, they found a match in the handwriting samples of the kidnapper and Bruno Hauptmann. He was sentenced to death and was executed on April 3rd, 1936.

Today, there are over 20,000 certified handwriting experts, or graphologists, in the US. It is estimated that about 5,000 corporations use handwriting analysis in different ways.

Uncovered :: False Analysis

Because there are over 300 million people living in America, the individuals analyzing the handwriting samples of evidence could falsely identify the given sample with the wrong suspect. For example, if Hamp and Whitney had handwriting that was a very similar, the analyzer could match up Hamp's ransom note falsely with Whitney's handwriting. Whitney would be accused and prosecuted for Hamp's wrong doing.

Uncovered :: Identifying Handwriting

There are many different techniques and indicators to look for in a sample of writing to identify who wrote it. I will explain 12 of those main points below.

1. Line quality: Do the letters flow or are they written with very intent strokes?

(Is the writing curvy and/or cursive like, or are straight lines used?)

2. Spacing of words and letters: What is the average space between words and letters?

(Are the letters really close, or further away? And the words? Paragraphs?)

3. Ratio of height, width, and size of letters: Are the letters consistent in height, width, and size?

(Are all of the letters approximately the same size, or are some bigger than others?)

4. Lifting pen: Does the author lift his or her pen to stop writing a word and start a new word?

(Is the writing all connected as if it was cursive, or is it all disconnected?

5. Connecting strokes: How are the capital letters connected to lower-case letters?

(Are the capitals connected to the lowers case is different ways? Are they even connected at all?)

6. Strokes to begin and end: Where does the letter begin and end on a page?

(Do they start at a certain margin? Maybe at the first red line, an inch or so from the first red line, or maybe they just start at the beginning of the page?)

7. Unusual letter formation: Are there any letters written with unusual slants or angles? Are some letters printed rather than written in cursive?

(Are certain letters different than all of the other letters?)

8. Pen pressure: How much pen pressure is applied on upward and downward strokes?

(Is the writing light, or does it seem to be pressed down hard?)

9. Slant: Do letters slant to the left or right? If slant is pronounced, a protractor may be used to determine the degree.

(Self explanatory.)

10. Baseline habits: Does the author write on the line or does the writing go above or below the line?

(Does the writing stay in the blue lines, or does it escape into the above/below lines?)

11. Fancy writing habits: Are there any unusual curls or loops or unique styles?

(Example: A curl at the end of a y. Or a loop-bottomed t.)

12. Placement of diacritics: How does the author cross the t’s or dot the i’s?

(Maybe they use hearts to dot the i's, or even a small circle instead of a dot.)