Monday, September 7, 2009
7 Quick Facts about Fingerprints
1. Some ancient civilizations used fingerprints as a way of sealing or signing official documents.
2. No two fingerprints are exactly alike
3. Has served all governments worldwide for the past 100 years
4. Fingerprints are the basis for criminal history foundation at every police agency on Earth
5. Remains the most commonly used forensic evidence worldwide
6. Tens of thousands are added to fingerprint databases daily in America
7. Worldwide, fingerprints gathered from crime "scenes lead to more suspects and generate more evidence in court than all other forensic techniques combined"
http://www.onin.com/fp/fphistory.html
http://odec.ca/projects/2004/fren4j0/public_html/history_of_fingerprinting.htm
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1. History of Fingerprinting
- 1686: Marcello Malpighi, a professor of anatomy at the University of Bologna, noted ridges, spirals, and loops in fingerprints. Although he mentioned this, he did not mention there value as a tool of identification.
- 1823: John Evangelist Purkinje published his thesis discussing nine fingerprint patterns but did not mention there value to identification.
- 1858: Sir William James Hershel first used fingerprints on native contracts. He only did this to scare the people for if they wanted to back out of a signed contract. This was the first way that the English used fingerprints as identification.
- 1882: Gilbert Thompson used his own thumb print on a document to prevent forgery.
- 1891: Juan Vucetic began the first fingerprint files.
- 1903: The New York State Prison system began using fingerprints for criminals.
- 1905: U.S. Army begins using fingerprints
- 1907: U.S. Navy begins using fingerprints
- 1908: U.S. Marine Corps starts using fingerprints
- 1946: The FBI had processed 100 million fingerprint cards in manually maintained files
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2. Types of Fingerprints
There are three kinds of fingerprints: Patent, latent, and impressed
1. Patent prints which are also known as visible prints are able to be seen with the naked eye. They can be when blood, dirt, ink or grease on the finger come into contact with a smooth surface and leave a friction ridge impression that is visible without development.
2. Latent prints are not apparent to the naked eye. They are formed from the sweat from sebaceous glands on the body or water, salt, amino acids and oils contained in sweat. The sweat and fluids create prints that must be developed before they can be seen or photographed. They can be made sufficiently visible by dusting, fuming or chemical reagents.
3. Impressed prints are also called plastic prints and are left in soft pliable surfaces, such as clay, wax, paint or another surface that will take the impression. They are visible and can be viewed or photographed without development.
http://odec.ca/projects/2004/fren4j0/public_html/types_prints.htm
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3. Techniques/Chemicals used to Devlop Prints
Silver Nitrate: This chemical is used to expose latent prints. This chemical is found in white and black photographic film. When silver nitrate is applied to a latent fingerprint, the silver nitrate interacts with the chloride found in fingerprint residue and forms silver chloride. The silver chloride reveals a black or reddish-brown fingerprint in the presence of ultraviolet light.
Sudan Black: This method develops fingerprints on a greasy or waxy non-porous surfaces such as glass, metal, interior of gloves, candles, and milk cartoons.
Zinc Chloride: This traditional method enhances prints on porous material after processing with Ninhydrin. Zinc Chloride is offered as a 1 liter solution in Methanol.
http://wiki.answers.com/Q/chemicals_used_in_forensic_studies
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4.Shapes and Patterns of Fingerprints
Arches are found in about 5% of fingerprint patterns encountered. The ridges run from one side of the pattern to the other and make no backward turns. There are four types of arch patterns: plain, tented, radial, and ulnar
Whorls are found in about 25-35% of the fingerprints encountered. Some of the ridges in a whorl make a turn through at least one circuit.Whorl patterns are any patterns that contain two or more deltas. There are four kinds of whorls also: Plain, central pocket loop, double loop and accidental.
Loops are seen in about 60-70% of the fingerprints encountered. One or more of the ridges enter on either side of the impression, re-curves, touches or crosses the line running from the delta to the core and terminates on or in the direction of the side where the ridge or ridges entered. each loop pattern has one delta, one core, and a ridge count. There are two types of this pattern: radial and ulnar.
http://odec.ca/projects/2004/fren4j0/public_html/fingerprint_patterns.htm
Pictures:
http://safety-identification-products.com/fingerprint-information.html
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5. Collecting and Lifting Fingerprints
New Method:
This new method is used on metals such as bullets and bombshells. The prints can still be identified even if they have been wiped or washed off. The way it is done is by applying an electrical charge to the metal which has been coated in a fine conducting powder. Even if fingerprints is washed off, there is still evidence of it there and once the powder attracts with the charge then it is visible.
http://www.policensw.com/info/fingerprints/finger12.html
Posted by D. Alex Pender at 8:01 PM 0 comments
Handwriting Comments
I really enjoyed the handwriting forgery assignment because I got to experience how hard it is to forge someone else handwriting. By doing that assignment I learned and concluded that forgery is really a skill and that handwriting analysts have a tough job because once that skill is mastered it is very hard to tell the difference between the original and the forged.
Posted by D. Alex Pender at 7:54 PM 0 comments
History of Handwriting
Before there was handwriting there was only verbal communication. Eventually systems of pictures were created. The Sumerians then began writing on scribes and later the Phoenicians created the first alphabet consisting of 22 symbols. The Celtics style of writing involved writing the letters in 1 inch square guides(unicals). Also in Charlemagne standardized writing they used both lower case and upper case letters (upper case used to start sentences). Around 900AD the Gothic style was introduced and it was very thick, angular, and tightly set, in order to save space. There was a common strict style and also a style that was more precise and artistic for important text. In the 10th century, the letter 'u' was created separately from 'v'. In the 12th century the 'w' was created in order to accommodate European languages and in the 15th century the 'j' was created. Then in the mid 1400's Gutenberg created the movable type press and in the late 1500's Robert Granjon designed type faces that resembled script writing. Around the mid 1700's people were able to go to school for penmanship and this showed a high social status. Charles Zanar and Elmer Bloser created materials and tools to teach good penmanship in the mid 1800's and then in 1904 the Method of Arm Movement was developed to help with elementary school children's handwriting. Lastly there was the D'Nealian style which uses slanted letters in order for children to transition into cursive easier.
http://www.vletter.com/handwriting.htm
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Techniques and Indicators
Analyst generally look four components when analysing a written document:
1) Form: shape, proportion, slant, lines, angles, retracing, connection and curves
2) Line quality: pressure, instrument used, continuity and flowing of writing
3) Arrangement: spacing, alignment, formatting, and punctuation
4) Content: spelling, phrasing, grammar, and sentence formation
http://www.enotes.com/forensic-science/handwriting-analysis
12 Basic Characteristics for Comparing Handwriting
1. Line Quality
2. Spacing of words and letters
3. Ratios of height, width , and size, of letters
4. Lifting pen
5. Connecting strokes
6. Strokes to begin and end
7. Unusual letter formation
8. Pen pressure
9. Slant
10. Baseline habits
11. Fancy writing habits
12. Placement of Diacritics
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Inaccuracy in Handwriting Analysis
Sometimes forensic investigators are not able to accurately identify handwriting because it may not be the original copy. The document may have been forged. Some people are so good at forgery that one can not even tell the difference in the handwriting. Also depending on if the person is consistent or not with their handwriting is another factor when it comes to identifying handwriting. Plus there are simpler factors like what the person writes on, if smudged, if typed, and what they write with.
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History of Hair and Fiber
Posted by D. Alex Pender at 4:16 PM 0 comments
Techniques used to Identify Hair and Fiber
Posted by D. Alex Pender at 4:16 PM 0 comments
- Black Male: dark, black lines/brown and red inside
- White Male: really thin green lines with a light yellowish-tan inside
- Synthetic: gray, thin lines with a dark black inside(not the road look)
- Asian: dark and black thick lines and brownish-purple inside color( mahogany wood look)
- Color treated: Thick middle equals a yellow color
- Dog: very thin gray and black with bubbles
- Cat: all black with bubbles and strings
Posted by D. Alex Pender at 3:53 PM 0 comments
Major Types of Blood
Type A: Positive(+) Negative(-)
Type B: Negative(-) Positive(+)
Type AB: Positive(+) Positive(+)
Type O: Negative(-) Negative(-)
Type Donate To Receive From
A A or AB A or O
B B or AB B or O
AB AB only Anyone
O Anyone O only
http://www.answers.com/topic/blood-type
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Comments on Blood Mixing and Transfusions
Type A (+) anti A serum: Fuchsia, or light reddish-pink color with precipitate (clumpy little white, gray particles floating around)
Type A (-) anti B serum: Orange-yellow color with no precipitate
Type B (-) anti A serum: Red- no precipitate
Type B (+) anti B serum: Yellow with precipitate (stringy looking piece, mostly in the center)
Type AB (+) anti A serum: Light blue with precipitate (little swirls and white specks)
Type AB (+) anti B serum: Yellow with precipitate (very small, mushy precipitate)
Type O (-) anti A & B serum: Orangish-Red with no precipitate
- Negative Blood Type: No precipitate
- Positive Blood Type: Precipitate
- Refers to either the presence or absence of the RhD antigens compared to the presence or absence of the other antigens of the Rhesus system
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Crime Scene Investigation-Data
1.Exh: 1A- Synthetic Hair (Kooladria Jones)
2.Exh: 2A- Male Black hair (Ralph Johnson)
3.Exh: 3A- "I have your diamond ring" (Ralph Johnson)
4.Exh: 4A- Type "A" Blood (Ralph Johnson/Jenny Cho)
5.Glass Hand print: -Ulnar Loop Thumb Print (Mike Kelly)
6..Man Foot Print
7.Mike Kelly Empty Wallet
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Crime Scene Investigation- Analysis
Thursday September 3, 2009:
Mike Kelly went into Ruth's Kitchen for his routine daily breakfast and forgot his wallet in his car. He parked his car in the back, in the grass. As he ate inside, Ralph Johnson and Kooladria Jones came and broke into his car. Kooladria Jones was Ralph Johnsons lookout as he wrote the, "I have your diamond ring" note and stole the contents of Mike Kelly's wallet. He had on gloves but as he hastily opened the car door, he unnoticeable cut his arm and dropped a small drip of blood in the car. Then they ran away. When Mike Kelly went to pay for his breakfast he noticed that he did not have his wallet and ran out to his car to get it. While quickly opening the door (touching the window due to moving so fast) he found that his wallet was there, but his money and his wife's new diamond ring, was not.
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Blog Comments
In your Blood analysis section, I like how you added the chart that shows which blood types can be tranfused which each other. -Tin Nguyen
I like how you included quick facts about fingerprinting on your blog as well as the History component, and I also agree with Tin, I like the Blood typing charts. -Lizzie Paluso
Similar to other comments the visuals in your blog such as the charts give you a great idea of the types of blood classes and their meanings. Like the way you have a lot of space in Blood Mixing and Transfusions. ~ Bob Smith
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