fingerprints basics for scouts

by Captain Russ LescaultAugust 2009

What are Fingerprints?

• Fingerprint Composition– friction skin– Epidermis– 98-99% water; – 1-2%

• fatty acids, • amino acids, • minerals

Fingerprints

Fingerprints have two important characteristics:

• Permanence and

• Uniqueness (Individual)

BasicsBasics• Fingerprints are permanent and unique to each individual.

•Every primate (humans, monkeys, chimpanzees, etc.) has friction ridges on the soles of their feet (footprints) and hands (finger and palm prints).

Monkey fingerprint



•The friction ridges are covered with oils, salts and amino acid, which can be transferred to a surface causing latent (invisible) finger, palm or footprints.

•Friction ridges (finger, palm and foot prints) start to form at 12 weeks gestation in the womb and remain

•They can even be more unique than DNA, in fact identical twins can have the same DNA, but completely different fingerprints



•The friction ridges are covered with oils, salts and amino acid, which can be transferred to a surface causing latent (invisible) finger, palm or footprints.

•Friction ridges (finger, palm and foot prints) start to form at 12 weeks gestation in the womb and remain

•They can even be more unique than DNA, in fact identical twins can have the same DNA, but completely different fingerprints Monkey fingerprint

Fingerprint Types

– LatentInvisible or almost invisible prints. If you pick

up a glass object, your fingers will leave a residue of perspiration and body oil in the pattern of your fingerprints. A chemical medium is used to develop the print (carbon, aluminum or florescent powders or other chemicals) and an image of each print is formed.

– patent– plastic

Fingerprint Types

– latent– PatentFingerprints that are made

when a hand has been dipped into paint, ink, grease, blood, or another opaque liquid, and then has touched something else.

– plastic

Fingerprint Types

– latent– patent– Plastic– Fingerprints that are left when a

person touches a semisoft, impressionable substance, such as putty, clay, plastic, dough, or wet plaster.

Fingerprint Processing: Types

• Powders– Black Powder– Magnetic Powder– Florescent Powder– Aluminum Powder

• Chemicals (lab)– Iodine Fuming– Ninhydrin– Chemprint– Silver Nitrate– Cyanoacrylate Fuming– Sticky-side Tape Solution

Fingerprint Fingerprint Identification BasicsIdentification Basics

Pattern types: there are three basic fingerprint pattern types, whorl (to the left), arch and loop.

Whorl:

swirling pattern

Loop

Pattern has a right or left slant (leans)


Arch

Looks like a ‘hill’


History of Fingerprints

• 1500 BC: In ancient Babylon, fingerprints were used on clay tablets for business transactions.

History of Fingerprints• 1500 BC: In ancient Babylon, fingerprints were used on clay tablets for business transactions.

•1000 BC: In ancient China, thumb prints were found on clay seals.

• In 14th century Persia, various official government papers had fingerprints (impressions), and one government official, a doctor, observed that no two fingerprints were exactly alike

•1856 - The English first began using fingerprints in July of 1858, when Sir William Herschel, Chief Magistrate in India, first used fingerprints on native contracts.


• 1500 BC: In ancient Babylon, fingerprints were used on clay tablets for business transactions.

•1000 BC: In ancient China, thumb prints were found on clay seals.

• In 14th century Persia, various official government papers had fingerprints (impressions), and one government official, a doctor, observed that no two fingerprints were exactly alike

•1856 - The English first began using fingerprints in July of 1858, when Sir William Herschel, Chief Magistrate in India, first used fingerprints on native contracts.

History of Fingerprints•1880 Henry Faulds, a Scottish doctor living in Japan began collecting fingerprints. By chance, he was asked to help investigate a crime in which very clear fingerprints in soot were left at a crime scene.

•He was able to convince the authorities that their number one suspect could not have left the prints, but a minor suspect must have left the prints.

•This was the first time a crime was solved based on fingerprint evidence. Faulds wrote a letter on the subject to the journal Nature, October 1880. Henry Faulds

(1843-1930)


Henry Faulds(1843-1930)

History of Fingerprints•1892 Sir Francis Galton’s contribution was to firmly establish that fingerprints are unique, using a simple yet elegant mathematical argument.

•1892 he published the book "Finger Prints“. Minutia are sometimes called “Galton Details” in his honor.

Sir Francis Galton(1822-1911)

History of Fingerprints•1892 Sir Francis Galton’s contribution was to firmly establish that fingerprints are unique, using a simple yet elegant mathematical argument. 1892 he published the book "Finger Prints“. Minutia are sometimes called “Galton Details” in his honor.

Sir Francis Galton(1822-1911)

History of Fingerprints•The first accepted scientific method of identification was developed by Alphonse Bertillon in the late 1800s.

•The Bertillon system relied on a combination of physical measurements taken by carefully prescribed procedures.

•, Bertillon could place the dimensions of any single person into one of 243 distinct categories

Used from 1882 to 1903


Used from 1882 to 1903

http://www.nlm.nih.gov/visibleproofs/media/detailed/iii_c_100c.jpg

http://www.nlm.nih.gov/visibleproofs/media/detailed/ii_c_304.jpg

History of Fingerprints•1897 Sir Edward Henry solved the fingerprint-indexing problem with an ingenious solution in 1897. Scotland Yard adopted the Henry-System in 1901.

•Since then, the system has been adopted by virtually every country in the world

Sir Edward Henry(1850-1931)

History of Fingerprints•1897 Sir Edward Henry solved the fingerprint-indexing problem with an ingenious solution in 1897. Scotland Yard adopted the Henry-System in 1901. Since then, the system has been adopted by virtually every country in the world

Sir Edward Henry(1850-1931)

History of Fingerprints•The Will West case

•Leavenworth, Kansas

•Will Wes arrived at the Federal Penitentiary in 1903. West denied any previous incarceration there; but when the record clerk took his Bertillon measurements, they matched those on file for William West.

• In addition, the photographs of William West looked identical to the new prisoner. But when the clerk turned over the card, it showed that William West was currently imprisoned in Leavenworth.


Fingerprints replaced the Bertillon systemFingerprints replaced the Bertillon system

Will West and William West had different fingerprints.


•1902 The first year for the first known systematic use of fingerprint identification began in the United States. The New York Civil Service Commission established the practice of fingerprinting applicants to pre-vent them from having better qualified persons take their tests for them.

•On 27th June 1902 the first conviction by fingerprint evidence in the US was obtained. Harry Jackson was given 7 years penal servitude for burglary


•1904 The fingerprint system accelerated when the United States Penitentiary at Leavenworth, Kansas, and the St. Louis, Missouri, Police Department both established fingerprint bureaus.

•1921 The growing need and demand by police officials for a national repository for fingerprint records led to an Act of Congress establishing the Identification Division of the FBI.

History of Fingerprints•1963 (JFK Assassination) Two fingerprints are found on the rifle taken from the sixth floor of the Texas School Book Depository. The first was located on the left side of the trigger housing of the rifle as it was held in a forward position. A second area containing a palm print was found on the underside of the disassembled rifle barrel. Both identified to Lee Harvey Oswald.

•1990s – AFIS, or Automated Fingerprint Identification Systems, begin widespread use around the country. This computerized system of storing and cross-referencing criminal fingerprint records would eventually become capable of searching millions of fingerprint files in minutes, revolutionizing law enforcement efforts.


1999 - The FBI phases out the use of paper fingerprint cards with their new Integrated AFIS (IAFIS) site at Clarksburg, West Virginia. IAFIS starts with individual computerized fingerprint records for approximately 33 million criminals.

•2002 – The FBI 50K study" took a set of 50,000 pre-existing images of fingerprints and compared each one electronically against the whole of the data set, producing a grand total of 2.5 billion comparisons. It concluded that the chances of each image being mistaken by the computer for any of the other 49,999 images were vanishingly small, at 1 in 1097.


•2008 - The FBI's master criminal fingerprint file contains the records of approximately 55 million individuals, while their civil file represents approximately 31+ million individuals.

Galton or identification points are readily definable areas where the ridge “or

lines” intersect or stop

What makes a What makes a Fingerprint Fingerprint

Comparable ? Comparable ?




Comparable ? Comparable ?



A comparable fingerprint has to have at identification points.


Comparable ?Comparable ?

Palm

Partial

Latent Fingerprint

This includes fingerprints, palm prints and partial fingerprints

Suspect’s fingerprint when he was arrested

Fingerprint found at the crime scene

They match!

What is AFIS ?

Automated

Fingerprint

Identification

System

Examiner Enters

Latent into AFIS

1) makes the decision if a latent is of AFIS Quality (a) 8 to 12 points (b) identifiable core or delta 2) If the system does not have a direct scan feature, they scan the print 5times it’s normal size

3) traces the print

What happens What happens now?now?

Examiner Enters

Latent into AFIS

Examiner :

1) makes the decision if a latent is of AFIS Quality (a) 8 to 12 points

(b) identifiable core or delta

2) If system does not have a direct scan featurem then they scans the print 5 times it’s normal size

3) traces the print

4) enters the scan or tracing into AFIS computer

Examiner Enters

Latent into AFIS

The AFIS computer automatically identifies The AFIS computer automatically identifies the Galton points and maps them into the the Galton points and maps them into the

computer, which is verified by the Examinercomputer, which is verified by the Examiner

Then what Then what happens?happens?

The AFIS system then

makes a match...• The Va AFIS system searches the 2.5 million fingerprints on file • The system generates a list of candidates (suspects)

• The Examiner then compares the listed candidates to confirm (or reject) if there is a match.

fingerprints basics for scouts

Education