Fingerprinting

HISTORY

Fingerprinting was first recorded in ancient Babylon around 1000-2000BC. The Babylonians used the method of fingerprinting as means of business transactions, by pressing their finger into a clay tablet. The Chinese had also used clay seals to identify their lost children, or to 'sign' documents around 3rd century B.C.

--(Clay fingerprint mold found in China)

After many centuries, a government official in Persia had discovered in the 14th century that no two fingerprints were the same and that all prints formed a unique pattern.These were then given names for its distinguishing features by an Italian professor Marcello Malpighi, who inspected the prints by the microscope that was still a relatively new invention in this time period. He noticed ridges, loops, and spirals in the prints and in respect, a layer of skin was named after him called “Malpighi layer”.

 In 1823, an anatomy professor John Purkinje published a thesis after furthering Malphighi’s studies of finding nine possible patterns of a fingerprint. However, this document was not recognized as a method of identification of people but as mere factual evidence. Forty years later Professor Paul-Jean Coulier published a finding on a preservation method of prints and also the potential for further identification of criminals by using a magnifying glass to examine their fingerprints. Dr. Henry Faulds applied printers ink to retrieve fingerprints and was the first to be able to identify them.

Mark Twaine, a notable author and also the creater of Tom Sawyer, introduced identification of the murderer by his fingerprint in the novel Life on the Mississippi and influenced the others to wonder if gathering fingerprints at the crime scene would lead to a successful arrest. Juan Vucentic first used this new idea to use and convicted Francis Rojas by the residue of her bloody fingerprint to the one that they had filed. Afterwards Sir Francis Galton published a book, Fingerprints, to provide a classification system for the fingerprints and to prove the permanence of the fingerprint by observing fingerprints while aging. He also solidified the uniqueness of each fingerprint and according to his research the odds of two people having the same fingerprint were 1 in 64 billion. India was the first to recognize this as a method to identify an individual and created a database of all the criminals' fingerprints, the most recognized being Calcutta Anthroprometric Bureau in 1897. Azizi Haque and Hem Chandra Bose developed the Henry classification system (named after their supervisor) to file the fingerprints.

In 1901, New Scotland Yard established a Fingerprint Branch following India's example, and also employed the Henry System of Fingerprint Classification. Three years later, the New York State Prison gathered the fingerprints of criminals and expanded throughout the country. International Association of Chiefs of Police (IACP) formed the National Bureau of Criminal Identification strictly for fingerprint identification.

Example of a fingerprint card used

Congress formed the Identification Division in FBI, and the criminal identification of IACP and Bureau of Criminal Identification were consolidated into one database. By 1987, this database grew into 200 million manually filed fingerprint cards. Automated fingerprint identification system was later developed and the 200 million cards were computerized. It was still not as effective as the programs of today because many of the datas were duplicated and there were glitches in the system.

TYPES OF FINGERPRINTS

The types of fingerprints can be distinguished in three broad groups;

Visible

• Also called patent prints
• left with a medium such as blood, ink, dirt, grease, etc.
• can be seen by human eyes

Latent

• Not seen by the naked eye
• formed from the sweat (or fluid contained in sweat) on the body  
• must be developed before they can be seen or photographed
• can be made visible by dusting, fuming or chemical reagents

Impressed

• also called plastic prints
• indentations left in soft surfaces, such as clay, wax, paint, etc.
•  can be viewed without development

DEVELOPING PRINTS ON SURFACES

There are four primary chemicals used in basic development of fingerprints. Those are

• iodine
• cyanoacrylate (super glue)
• silver nitrate
• ninhydrin

Some of the minor chemicals also used are listed below

• diazafluoren 1 (DFO-1)
• rhodamine
• ardrox
• sudan black
• thenoyl europium chelate (TEC)
• acid fushin

Porous-
 paper, unfinished wood, cardboard... can easily preserve because the latent print can soak into a surface

Non-absorbent
plastic, glass, metal.... fragile evidence and can be easily ruined or wiped away

Hard surface
asphalt, concrete- difficult to collect fingerprint from because it is not completely smooth, and the print is likely to be disfigured

Smooth surface
Smooth surface such as glass, wood, plastic, etc in which fingerprints can be easily lifted from.
Methods to Develop
Cyanoacrylate is used to 'fume' fingerprints onto the surface. To do this, the smooth surface with fingerprint needs to be contained in a jar with a couple drops of cyanoacrylate in it. After about five minutes, the print would've developed on the microscopic slide and you have your evidence! Iodine goes through the same procedures, with the fuming method.

Silver Nitrate reacts with the sweat contained in the fingerprint and it should be sprayed onto the print after being diluted by water or alcohol.

Ninhydrin also reacts with amino acid (sweat) but the prints will come up in purple, and take about 24 hours for it to develop after the prints are sprayed with a generous amount of Ninhydrin.

 

BASIC SHAPES/PATTERNS OF FINGERPRINTS

The patterns of fingerprints can be categorized into three types: arches, loops, and whorls.

Fingerprints can be distinguished by its unique patterns. Although fingerprints differ for each individual person, every human being has one of nine patterns established by Purkinje on their print. The nine patterns are condensed into three main patterns: archs, whorls, and loops.

The Arch

About five percent of the fingerprints are archs, one of either plain arch or tented arch. In an arch, the ridges of the print lies on top of one another forming a semicircle pattern on the surface. There are typically no deltas found within this pattern. There are two types of archs: plain arch and tented arch.

Plain Arch- even flow of ridges       

Tented Arch- makes a triangle shape within the ridges

Note: within the tented arch there can be radial and ulnar
radial- points to the right
ulnar- points to the left








The Loops
Loops occur in 60 to 70 percent of all fingerprints. In a loop pattern, the lines start from one side of the finger and revert back in the direction they started from. There are specifically two types, radial and ulnar.

Radial Loop and Ulnar Loop

Radial loop receives its name from the radius bone in the arm, and that is a good way to remember. Ulnar loop receives its name from the ulna. The ulnar loop always starts on the outerside of the hand, at the pinky, and the radial loop starts at the inner side of the hand towards the thumb.

Central Pocket Loop

Central pocket loop consists of multiple free curving ridges and two deltas. It almost looks asthough it is a complete circle on your fingerprint.

Twinned Loop (Double loop)

In a twinned loop, the two loops link together to make an 'S' shape on the print. There are two deltas residing in this particular pattern.

The Whorls
The whorls are seen in 25 to 35 percent of all fingerprints. Any fingerprints consisting of two or more ridges are considered a whorl.

Plain Whorl

In a plain whorl, the deltas make a complete circuit creating a circular print.



Fingerprint Lab

In this lab, we stamped our fingerprints onto a sheet of paper used for criminals to record their prints.

Most of the fingerprints I had were either ulnar loops, or radial loops. No whorls were found in my prints and two arches were found on the right hand.

HOW TO COLLECT/LIFT PRINTS

1. Coat the present fingerprint with powder; talc if on dark surface and granite if on light surface.
2. Brush over the print gently without disturbing it with soft brush made of either camelhair or a regular fiberglass brush.
3. Place the sticky side of a transparent tape on the dusted fingerprint
4. Tape the print onto a contrasting colored paper.

Lifting Fingerprint Lab

Using the above procedures, we conducted an experiment in lab using granite.

To obtain oil to make our fingerprint visible, we rubbed our finger on either the side of the nose or the forehead to obtain natural oil collected on the body.  The granite powder was not fine enough for it to leave a complete print on the tape. A lot of them were little pebbles, interfering with the lifting. The one to the far right was the best out of all, because the pattern was visible.

Bibliography

http://www.odec.ca/projects/2004/fren4j0/public_html/types_prints.htm

http://thumbs.dreamstime.com/thumblarge_409/1244836472mo934k.jpg

http://www.joplinglobeonline.com/blogs/scott_blog/?entry=entry090813-132157

http://www.anilaggrawal.com/ij/vol_002_no_001/papers/paper005.html