Monday, September 7, 2009

Hair and Fiber

History of Hair and Fiber:


1879 Rudolph Virchow, a German pathologist, was one of the first to both study hair and recognize its limitations


1910 Victor Balthazard, professor of forensic medicine at the Sorbonne, with Marcelle Lambert, published the first
comprehensive hair study, Le poil de l'homme et des animaux. In one of the first cases involving hairs, Rosella
Rousseau was convinced to confess to murder of Germaine Bichon.


Techniques used to Identify Hair/Fiber:

Microscope:
-1 analyed
-2 compared

Nuclear DNA and Mitochondrial DNA (mtDNA) tests
-More information on culprit unable to be obtained from microscopic view.

1. Human or Animal? Determine this first to get some general information
2. The hair could have been shed or forcefully removed; if the latter of the two you would know violence had occurred.
3. Figure out which part of the body the hair came from could provide good evidence.
4. You should be able to tell through the hair the racial background of the person whom the hair belongs to.
5. You can also tell how long ago the hair was dyed by how much of the hair isn't treated.


Lab Findings:
If you can adjust the microscope well, this could be a excellent piece of evidence. It can show material types, person's hair color, person's drug history, or animal hairs. All this information helps on finding the criminal.

Guess on how the crime occurred:

One evening while driving home in the rain, Mike Kelly spotted a woman walking without an umbrella. He invited her into his car and by the end of the car ride, convinced her to spend the night. The arrived at his house around 11:00 pm and went straight to bed. When Mike Kelly woke up, the woman had a gun to his head demanding all his money; for she was the notorious Koolanda Jones. The criminal mastermind Mike Kelly activated the metallic ceiling with a voice command. This cause Jones's gun to be ripped from her hand to the ceiling and the bullet shot to skim Kelly's left ear. He pulled a gun out of a secret compartment and aimed at Jones. She quickly turned around as he fired and her bulletproof hair stopped the shot. She quickly turned and ran at Kelly; but he whipped out one of his tennis rackets and sent her spawling across the floor. He then, now infuriated, mercilessly beat her face. The police came soon after recieving complaints about gunfire from neighbors; Mike Kelly was forced to flee.


This information was derived from the following sites:


http://www.forensicdna.com/Timeline020702.pdf

http://www.fbi.gov/hq/lab/fsc/backissu/july2000/deedric1.htm#Hair

Blood Typing

Major Types of Blood

A(+/-): Contains "A" agglutinogens only.

B(+/-): Contains "B" agglutinogens only.

AB(+/-): Contains "A" and "B" agglutinogens.

O(+/-): Contains neither "A" nor "B" agglutinogens.


Difference between Positive and Negative Blood Types

Positive Blood types contain Rh protein and the Negative Blood types do not contain Rh protein.


Blood Mixing and Transfusions


As demonstrated below, all the negative blood types can only recieve negative blood. Considering this, with O being able to give to any type, O- can be injected into anyone; this works exceptionally well in an emergency when the patient has lost a lot of blood. Also, the reason why some blood mixes don't work is because of antibodies that attack the the blood cells that contain their type of agglutinogens.


A+:

Contains B antibodies.

Can Recive Blood from: A+, A-, O+, O-.


A-:

Contains B antibodies.

Can Recive Blood from: A-, O-.


B+:

Contains A antibodies.

Can Recive Blood from: B+, B-, O+, O-.


B-:

Contains A antibodies.

Can Recive Blood from: B-, O-.


AB+:

Contains no antibodies.

Can Recive Blood from: A+, A-, B+, B-, AB+, AB-, O+,O-. (Any)


AB-:

Contains no antibodies.

Can Recive Blood from: AB-, A-, B-, O-.


O+:

Contains both A and B antibodies.

Can Recive Blood from: O+, O-.



O-:

Contains both A and B antibodies.


Can Recive Blood from: O-.


Lab Findings:

I learned that blood type is slightly helpful in determining a culprit in a crime. But the fact is that there are only eight types of blood; and it doesn't really pinpoint a suspect unless you have narrowed it down already.

This information was derived from the following sites:

http://chapters.redcross.org/br/northernohio/INFO/bloodtype.html

http://learn.genetics.utah.edu/content/begin/traits/blood/

http://nobelprize.org/educational_games/medicine/landsteiner/readmore.html

Tuesday, September 1, 2009

History of Handwriting

The Jews were the first to notice the differences in people’s handwriting. This recognition was codified in the Jewish Mishnah in the first and second centuries. This individuality has led to the making of a pseudoscience called graphology. In graphology, you are able to derive someone’s personality from their handwriting. “Grapghological methods have little if any experimental foundation, but the work of the questioned-document examiner is established on sound principles: it relies on empirical principles, is self-correcting, and is self-policing (involving peer review and other policing mechanisms)”-British expert William R. Harrison. The first time handwriting was crucial to a widely famous case was during the Dreyfus affair of 1894-1895. A French army officer, Alfred Dreyfus, was arrested, tried and convicted of spying on the basis of a forged letter that indicated his treason in giving important military secrets to Germany. Sadly, the great criminalist, Alphonse Bertillon, whose testimony was needed to secure Dreyfus’s conviction, lacked enterprise in the field of handwriting comparison. He then tried to apply principles from his own science of anthropometry. After only twelve years of controversy, Dreyfus was declared innocent and freed from prison. In American history, the first use of handwriting analysis was in the Lindenbergh kidnapping case. The ransom letters by Bruno Richard Hauptmann contained the same mistakes and writing style he used normally; this gave him away with the support of other evidence.

This information has been derived from:
http://books.google.com/books?id=QEpgv0X6BVQC&pg=PA168&lpg=PA168&dq=history+of+handwriting+with+crime&source=bl&ots=yt9U1mRLFd&sig=tqKzxX9imxSOvxJ29OoqMruQ6nk&hl=en&ei=4rGaSvy1NI6e8QbP4dy3BQ&sa=X&oi=book_result&ct=result&resnum=1#v=onepage&q=history%20of%20handwriting%20with%20crime&f=false

Techniques or Indicators scientists use to identify handwriting or forgeries

Scientists look for:




-Signs of Alteration, forgery, and (when sample documents are availible) handwriting or typing comparisons to determine or rule out authorship.

-Differences, not simularities.



-Style Characteristic vs individual characteristics.


*** Style characteristics are only useful for determining which copybook the writer learned from.


*** Individual characteristics are what matter most in determining authorship; they are unique to us and distinguish us from others.




This information was derived from:



Wednesday, August 26, 2009

Procedures for collecting/lifting fingerprints

1. Photograph any visible fingerprints that you observe.

2. Carefully dip the brush into the appropriate powder. Apply a small amount of powder to the tip of the brush.

3. Apply the powder to the surface with a light twirling motion over the area to be processed. If a heavy deposit appears on a fingerprint, gently brush off the excess powder with a light twirling motion.

4. Photograph any latent fingerprints that have been developed.

5. Apply a short piece of lifting tape. This must be pressed well onto the surface.

6. Slowly remove the lifting tape from the surface and place it on a backing card that is of contrasting color to the powder being used.

7. Properly fill out the back of the backing card with the proper information.

This information was derived from:
http://www.csigizmos.com/products/latentdevelopment/processing.html

Basic patterns/shapes of fingerprints

Left-leaning loop:

Right-leaning loop:

Whorl:


Double loop:


Double loop with central pocket:


Plain arch:


Tented arch:


Arch with loop & scar:


This information was derived from:

Chemicals/tecniques used to develop fingerprints

When the surface is

Nonabsorbant(2 methods):
-Black powder-black carbon or charcoal for light sufaces
-Gray powder-aluminum dust for dark sufaces.

Porous(3 methods):
-Iodine fuming (has the ability to sublime)
-3% solution of silver nitrate
-0.6% ninhydrin powder dissolved in acetone or ethyl alcohol.

Hard(2 methods):
-Black powder-black carbon or charcoal for light sufaces
-Gray powder-aluminum dust for dark sufaces.

Smooth(3 methods):
-Iodine fuming (has the ability to sublime)
-3% solution of silver nitrate
-0.6% ninhydrin powder dissolved in acetone or ethyl alcohol.

The previous information was derived from:
http://www.bxscience.edu/publications/forensics/articles/fingerprinting/f-fing03.htm