Criminalistics

You may use outside sources for your answers to this exam with four (4) caveats.  1. Your outside source CANNOT be Wikipedia.  If you use Wikipedia, you will receive a ZERO for that question.  2. You must cite your outside sources. 3. You cannot use ANY quotations; all of your answers must be only in your own words. 4. You cannot collaborate with anyone else: while you can use outside sources, those sources cannot be persons.

Class vs. Individual Characteristics (10 points)

Define class characteristics and list two (2) examples.  Define individual characteristics and list two (2) examples.  From the following photos, discuss the class and individual characteristics.

Fingerprint Examination (10 points)

Scenario:  You arrive at a breaking and entering to process the scene.  The glass to the back door of the residence is broken and it appears that the suspect may have cut his thumb or finger.  The suspect has taken a lap top computer that was sitting on the dining room table.  No other items are missing from the residence.  The suspect exited through the back door.

List and describe the 3 main types of evidentiary fingerprints that may be found at a scene?  Describe the types of fingerprints may have been deposited in this scenario?  What causes a fingerprint to be deposited on a surface?

Forensic Databases

1. List the name of the database used in the following departments and the type of information that is contained in each database.  (4 points)

2. What is a database?  How do the forensic databases work?  How is a forensic database useful for casework examination?  (6 points)

Hair Examination (10 points)

Scenario:  A woman is walking to her car which is parked in a parking garage.  She is approached from behind.  The person places his arm around her neck and is holding a sharp object against her neck.  He asked for her purse.  As he is trying to remove it from her arm with his other hand, she reaches back and grabs his hair.  He takes off and she is unable to describe her attacker.  However, she has a few of his hairs in her hand.

Describe the three morphologic components of hair.  List and describe the three stages of hair growth.  What can be determined from the hair evidence the victim recovered?  How would you examine the hair the victim recovered?

Glass Exami
nation (10 points)

Scenario: – A hit and run occurred, where the victim was found dead only a roadside.  She was known to walk home from work and was last seen around 11pm as she left work.  Approximately 11 days later a possible suspect was identified.  A preliminary exam of his vehicle showed considerable damage to the top and side of the driver’s side front fender.  A headlamp was missing.  This was an older vehicle, which had two (2) headlamps one above the other.  This is an example of how the headlamps would appear on the vehicle examined.

Exam of Suspect’s Vehicle:

No biological evidence (blood, skin, hair) was identified on the vehicle;

The vehicle appeared to have been washed and cleaned thoroughly;

There were fragments of broken glass lodged in the bumper and inside the area of the missing head lamp;

Paint samples were collected from the vehicle;

Samples of debris from underside of vehicle were collected as an exemplar (known, standard).

Laboratory Request:

Determine if there is an association between the glass fragments from the scene (where victim was found) and the fragments collected from the vehicle (bumper and area of missing head lamp).  Nine fragments were recovered from the scene and ten fragments from the vehicle.  It was noted that the manufacturing imprinted numbers and letters were visible in the glass fragments.

What is glass composed of?  How are automobile headlights manufactured?  Describe the techniques are used to compare glass fragments?  Discuss the limitations of glass examinations.  Describe how the glass in this case would have been examined.

Fingerprint Examination (10 points)

1. What is the importance of the ridge characteristics (minutiae) for a fingerprint examination?

2. In the following figure, identify 12 ridge characteristics:

Paint Examination (10 points)

What is the composition of paint?  List the four organic coatings used in automobile paint.  How can paint evidence be examined?  What is PDQ and what does it contain?

Fiber Examination (10 points)

Describe the difference between natural and manufactured (synthetic) fibers.  Give examples of natural and manufactured (synthetic) fibers.  Describe the basic chemical structure of manufactured (synthetic) fibers.  Discuss the examination of fibers.

Firearms Examination (10 points)

Markings/striations left behind on a projectile/bullet and the cartridge casings may link evidence to a particular firearm.  List and describe in detail the different types of markings/striations that may be left behind on a projectile/bullet and cartridge casings.

Tool Mark Examination (10 points)

What is considered a tool mark?  How is a tool mark created?  What type of crime scenes are tool marks mostly commonly found?  How is tool mark evidence collected?  Discuss the class and individual characteristics that may be found on a tool mark.  What type of trace evidence may be found on a tool mark?