Sunday, December 4, 2011

Introduction into Forensics

What is Forensics? The study of forensics has been proven very useful when solving criminal cases. It is nearly impossible for someone to commit a crime without leaving a trace of evidence. Anything left could be used to identify them; a fingerprint, strand of hair/fiber, lipstick,a note, or even a footprint. Don't know how these could possibly help you? Don't worry, that's why you're reading my blog.

Forensics: Hair/Fiber Analysis

History:
Hair and Fiber analysis is a field in forensics that has evolved and become key as evidence in trials across the nation. Hair and fiber analysis has played an important role in solving crimes, used in the Leo Rank Trial of 1913 to match the hairs of the victim with the crime scene. Hair analysis was also used in the Trial of Sacco and Vanzetti to match hairs found in a cap to those taken from Sacco.




Different Hair/Fiber samples:




















In the Lab we were to test several different hairs to see the different patterns of the hairs and fibers. 


Fibers: 
-Polyester 















-Cotton 

-Wool

-Rayon 

-Silk


How do Scientist analyze hair and fibers?

 Most comparisons of hair and fiber are done with a microscope, although fibers can be run through a spectrometer to determine an unknown material.  Samples from the suspects should number from about 15-25 strands from different locations so as to receive an accurate match.


Landmark Case:

One of the most famous cases involving Hair or Fiber Analysis was the Atlanta Child Murders case. Victims were found in rivers wrapped in shower curtains. The fibers proved a perfect match to a very unusual carpet in the murderer's home(a yellow rug), after testing the criminal was discovered. This was the first case in which the murderer was indentified from fibers found.



Forensics: Lipstick Analysis

For the lipstick part of the forensics subject we were asked to place our lip print on a index card. 
Then we were supposed to observe the indent and make note of our prints. 
For the lab part of the assignment we were instructed to work with our table and place all four of our prints on a sheet of paper and allow another group to match each other's prints. 

This lab was able to teach us that even a lip print can help investigators find a suspect. 

Forensics: Handwriting Analysis

History:
The use of handwriting has been used by investigators for many different cases. In 1611, Prospero Alorisio's manuscript was the first book to analyze handwriting. Later on, in 1976, the Council of Graphological Societies formed from the unification of the American Handwriting Analysis Foundation and the American Association of Handwriting Analysis.

Characteristics of Handwriting:

1. Line Quality- Do the letters flow or are they deliberately written?
2. Spacing of Words and Letters- What is the average space between words and letters?
3. Ratio of Height, Width, and Size of Letters- Are these consistent throughout document?
4. Lifting of the Writing Instrument- Is the instrument lifted to form a new letter/word, or does it stay on the page?
5. Connecting  of Strokes- Are the capital and lower case letters conected?
6. Stroke From Beginning to End- Where does the individual letter begin and end?
7. Usual Letter Formation- Are the letters written in unique ways/ formats?
8. Pressure- What is the ratio of pressure to upward and downward strokes?
9. Slant- Do the letters slant to the left, right, or not at all?
10. Baseline Habits- Is the writing on, below, or above the line?
11. Fancy Writing Habits- Are there noticable curls or loops?
12. Placement of Diacritics- Where does the writer cross the t's or dot the i's?

Famous Forged Case:
In the 1920's the Oliver Will case was tried in White Plains, New York where the question about a date on which a will was written. The top of the form of which the title and date were supposed to be had been torn off. There were two possible dates of which the form was created; January 8, 1924, or October 8, 1924. The date of the alleged will was September 20, 1924. Upon examination it was discovered that in tearing away of the dated portion of the form, the tail of the comma in the address was still visible. The position on the paper of that comma tail proved that the form could not have been the January 8th form. Therefor they were able to prove the will was forged.


Lab:
For the lab we were supposed to write an statement for in print and cursive and pass it to a partner. Then our partner was to observe our writing and try to forge it. The purpose of the assignment was to see how forgery is observed by crime scene officials. It can be used for suicide notes, kidnapping notes, forged checks, etc. . .

Forensics: Footprinting

To begin the lab we were asked to place our foot into a bucket filled with dirt and then take measurements of it.
This was my foot. As you can see the bottom was just a roundish indent. The reason behind that was I was wearing heels that day. 

Length: 8 in
Width: 4.5 in 
Position in track series: Straight
Depth of heel: 1 in

This activity helped us see how a footprint left could possibly help us identify a suspect.  

Forensics: Create a Profile

For this assignment we were asked to identify different clues to create a conclusion to a crime scene.
Analyzing Clues:
Clue 1:  Fingerprints
1-Plain Whorl
2-Central Pocket Loop
3-Central Pocket Loop
4-Ulnar Loop

Clue 2: Hair
Caucasian (Long) Long (Female?)

Clue 3: Handwriting
"You will never find her!
-mix of print & cursive
-large loops
-no lifting of pen
-consistent spacing
-dots are high and shifted right.
-flows well/quick writing.

Clue 4: Hair
Short, black towards end, white towards root.
Cat Hair

Clue 5: Lipstick
No definite shape

Initial Profile: The female victim was kidnapped, possibly wearing pink lipstick.

Forensics: Witness Experiment

For this exercise we were asked to get four similar-sized photos of people's faces. We had cut out different parts of the people's faces and pass them to someone else to put together.. The purpose of the assignment was for people to connect a person's face to a previous memory by certain aspects such as big eyes, a dimple, scar, etc. . .



Forensics: Drug Analysis

For this exercise, we were asked for background knowledge of cocaine, LSD, and meth. Information gathered:
Cocaine:
     Correct Chemical Name: benzoylmethylecgonine
     Correct Chemical Formula: C17H12NO4
     pH: 7.2
LSD:
     Correct Chemical Name: Lysergic Acid Diethylamide
     Correct Chemical Formula: C20H25N3O
     pH: 4
Meth:
     Correct Chemical Name: N-methyl-1-phenyl-propan-2-amine
     Correct Chemical Formula: C10H15N
     pH: 12.8

Lab: 
For this lab we were supposed to go to each section and test each of the unknowns for one of the drugs. 
Results: 
Drug     pH           Cocaine           LSD           Meth
1           4           Negative           Negative      Positive 
2           9           Positive             Negative      Negative
3           3           Negative           Positive        Negative
4           8           Positive             Negative      Negative
5           12         Negative           Negative      Positive
6           4           Negative           Positive        Negative



Forensics: Poison

What is a poison?
A poison is a substance that can cause disturbances to organisms, usually by a chemical reaction, when a sufficient quantity is  consumed by that organism.

Some common sources of poison:
-Medicine (overdose of prescriptions, etc..)
-Bites (venom from snakes, spiders, etc..)
-Food (rotten/raw, allergies )
-Household Products (ammonia)
-Plants (Poison Ivy)
-Carbon Monoxide
-Lead

Signs of Poisons:
-Foaming/Drooling
-Rash/Bruising
-Excess Vomit
-Increased Heart Rate/ Breathing
-Enlarged Pupils 
-Busted Blood Vessels (Bleeding under skin) 
- Discoloration to skin.

Lab: 
For the lab we were asked to identify which substance was a certain poison out of several unknowns, with the help of various reagents. 

1. Metal Poisons: 
Information given:
      1- Chromium would turn orange when acidified. 
      2- Lead forms a yellow precipitate when KI is added.
      3- Iron turns red (blood red) when KSCN is added.
Results: 
Unknown 1:  Lead (Pb) 
Unknown 2: Iron (Fe) 
Unknown 3: Chromium (Cr)

2. Sugars:
Information given: A purple color should form when sugar is present in the unknown.
Results:
Unknown 1: Negative
Unknown 2: Negative
Unknown 3: Negative

3. Household Ammonia:
Information given:
      1- Odor present
      2- pH over 7 (basic)
      3- Phenolthaline is pink/purple in solution (solution is basic)
Results:
Unknown 1: Negative
Unknown 2: Positive for all three test.
Unknown 3: Negative

4. Aspirin:
Information given:
     1-Bromythymel Blue will be yellow (acidic)
     2- pH is below 7. (acidic)
Results:
Unknown 1: Bromythymel blue turned the solution yellow. pH was 2. (acidic)
Unknown 2:  Negative. pH of 8.
Unknown 3:  Negative. pH of 8.

5. Cyanide:
Information given: Solution turns blood red when Fe+3 is added

6. Iodine:
Information given: Turn a blue/black color when starch is added.
Results:
Unknown 1: Negative. (remained yellow)
Unknown 2: Negative. (remained red)
Unknown 3: Positive. Solution turned blue.







Forensics: Crime Scene

For the final part of our Forensics we had to complete an entire crime scene. We had to complete several different tests such as reading prints, testing poisons, etc. . .

Set of Clues:
1-  Handwriting: Forged "Please forgive me. I love you all. "
  Large Loops, Semi-Connected letters.
  Handwriting changed throughout note.

2- Hair: Caucasian








3- Fingerprint: Plain arch





4-Poison?: Cocaine=Positive. pH between 7-8








5/6- Pictures: Maggots/Decayed face. The maggots show that the victim is in the "active decay" stage. This means the body was found approximately 20-50 days after the victim was killed. The face/body has undergone botynic fermentation.








7-Footprint of Victim:
    Height: 6 7/8 inch
    Width: 4 inch
    Athletic/Running Shoe
    Small shoe, child?



7- Footprint: 
     Height: 11 inch
     Width: 4 inch
     Athletic/Running shoe



8- Fingerprint: Ulnar Loop







9- Fingerprint: Double Loop







10- Fiber: Black long string. Nylon.






11-  Syringe: Could have been used to drug the victim.










Suspects
Courtney Smith                                            Jet Trong                                         Lucas Moore

Lucas Moore matched all the characteristics of the murderer.

Conclusion: 

Lucas Moore's wife divorced him, and took their young son with her. Soon after he fell into a deep depression, went crazy, and was admitted into a pchysiatric ward. He broke out and stole cocaine. He left a suicide note for the mother, planning to take his child. He waits in the woods for his son to pass by on his way home froms school. Spotting his son, Moore jumps out of the woods and tries to take the boy. The child fights back, which explains the missing tooth of the victim and the handful of short, caucasian hair. Moore tried to drug his child, but accidentally killed his son during the stuggle, so he left his son on the field by the edge of woods and the fled the seen.


Monday, November 28, 2011

Forensics: Fingerprinting

Finger printing has been a vital source of identifying for many centuries. A finger print is the pattern of someone's finger tip. The use of fingerprinting is very well known and used because no two people contain the same pattern, and the odds of that happening are very high.
History:

-In Ancient Babylon,  finger prints were collected when completing business transactions on clay tablets.
-14th Century Persia: Discovery, that no two fingerprints are identical.
-1823: John Evangelist Purkinje published a thesis about 9 fingerprint patterns, but also made no mention of fingerprints value in identifying people.
-1858: Sir William James Herschel begins to use fingerprinting on native contracts.

-1882: Sir Francis Galton, compiled a database of 8,000 fingerprints for further research into identification. Galton published Fingerprints, which was the first system for observing Fingerprints.

-AFIS (Automated Fingerprint Identification Systems): A database that automatically connects an unknown print to another known print. This system has since been used to identify many suspects.

Types of Prints


a. Latent : Partial prints left by the skin. May be smudged, distorted, or overlapped. Contain less clarity when observing because of the difficulty of reading.

b. Plastic : A print that when lifted contains the shape. Common examples are wax and putty.
c. Patent: A print of which is visible to the human eye. Some of the more obvious examples of a patent print are wet clay or possibly flour. Because of the visible nature the print can be photographed instead of lifted. Can be left on surface from ink, dirt or blood.
c. Direct/Exemplar: Known prints collected from a subject, such as when you apply for a passport.




Techniques/Chemicals used to develop prints on nonabsorbent, porous, hard, and smooth surfaces.
a. Black Powder(Charcoal or Carbon) is applied to light surfaces when lifting prints.
b. Gray Powder( Aluminum dust) is applied to dark surfaces.
c. Iodine is applied to surfaces, when heated the vapors will make the prints visible.
d. Silver Nitrate is used when lifting latent prints.

Basic Shapes/Patterns of Fingers
a. The Arch: made up of ridges lying above each other in an arch formation.
b. The Tented Arch: One upthrusting ridge that bisects the other ridges at basically right angles.
c. The Loop (Ulnar or Radial): Contains one or more recurving (free) ridges and one delta.
i. Ulnar: ridges flow from the side of the little finger.
ii..Radial: ridges flow from the side of the little finger.
d. The Whorl: Spiral formation.
e. The Twinned Loop: Two loop formations, separate and apart. Two Delta Points.
f. The Central Pocket Loop: Two delta points and consists of one or more free recurving ridges.
g. The Accidental: Two points of delta. One related to a recurve, the other related to a upthrust.








Procedure for collecting/lifting fingerprints:
Solid Dark Colored Surface:
1: Find a good print.
2: Use a white powder, such as talc, and gently cover the entire fingerprint with it.
3: Lightly blow off the excess powder. There should now be a visible print.
4: Using a clear piece of tape, cover the entire area to transfer the print off of the surface.
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):
1: Find a good print.
2: Use a dark powder, such as graphite, and gently cover the entire fingerprint with it.
3: Lightly blow off the excess powder. There should now be a visible print.
4: Using a clear piece of tape, cover the entire area to transfer the print off of the surface.
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.


Lab: 
We began our lesson on fingerprints when we stamped our prints using an ink pad. 
In class we were supposed to be able to lift our prints from various surfaces. 
For example we had to collect our prints from a dark surface using a light powder. 
My fingerprint
If you look you will see that the fingerprint I lifted was my right thumb. 


The Second part of the lab we completed was lifting our prints from a light surface using a dark powder such as graphite. 
The middle print of all three collected was my left thumb. Can you see the connection?


Overall this project was very difficult because of the difficulty lifting the prints.