Case Study # 5

Police receive a letter from an 8 year old girl that goes by Lauren. Lauren has been missing for 3 weeks. It had been presumed that she was kidnapped because on the day she went missing, her dad was released from prison. In the letter, the girl states that she is fine and requests that police call off the search for her. It also states that she has found a new home where she will be taken care of. The entire letter is written in cursive, contains no grammatical errors, and is signed Ellie (her first name that no one calls her).

Case Study # 5: Review Questions

1) Why was it presumed that Lauren was kidnapped?

2) Who is the prime suspect in the crime? 3) What is suspicious about the way the

letter is written? 4) What is suspicious about the way the

letter is signed? 5) How could investigators verify that this

is indeed Lauren’s handwriting?

Chapter 3

Fingerprint Evidence

Forensic Vocabulary

Morphology: branch of Biology that deals with form and structure of organisms

Questioned document: any document that is suspected of having been part of a crime

Serology: the science of examining different characteristics of blood

Forensic Vocabulary

Solute: a dissolved substance

Solvent: liquid substance capable of dissolving another substance

Fingerprints

Impressions left by ridges of the human finger.

The ridge is the raised portion of the epidermis on the digits.

Epidermal Ridges

Raised portion of the epidermis.

Epidermis: composed of the outermost layers of cells in the skin

The epidermis is important because: Prevents pathogens from entering the body Regulates the amount of water released from

the body

Epidermal Ridges

Fingerprints can be left behind due to the following: Oil Sweat Ink

Dactyloscopy: science of hand-print identification

Case Study # 6

A letter to police has just been received from an unknown source. The letter details numerous murders as well as other crimes that the author has committed. There is no return address and no signature. The letter is written in cursive with an unusual ink from a pen only sold in India.

Case Study # 6 Review Questions

1) Why is the letter so important to police?

2) If you were leading the investigation, which way would you attempt to locate the suspect?

3) Could fingerprint evidence be useful in this case? How?

4) Is fact that the ink is unusual have any importance to the case? If so, how?

Case Study # 7

Police have placed a house under surveillance. They believe that this house has strong drug activity. Police are afraid if they position cars outside the house on the street, then they will be spotted. The owner of the house has been arrested before for selling illegal drugs. The co-owner of the house has a clean record and drives an 18-wheeler across country for a living.

Case Study # 7 Review Questions

1) Is it possible for police to watch the suspect without parking on the street? How?

2) Does the co-owner of the house have anything to do with the case?

3) Do police have a right to kick in the suspect’s door and search his house? Why or why not?

4) If you were the lead detective on the case, how would you set up the surveillance/investigation?

Fingerprints

One unique property of fingerprints is that no 2 people have the same one.

This unique property is due to the flexibility of the epidermal ridge as well as the patterns on the finger.

Fingerprint Identification

Also called “individualization.”

Involves an expert or expert software system.

Very useful tool to forensic scientists because fingerprints are an individual characteristic of evidence. No 2 people will have fingerprints that are

100% matches.

Types of Prints

There are different types of fingerprints: Exemplar Latent Patent Plastic

Exemplar Prints

“Known prints”

Fingerprints collected from a suspect.

Includes one print taken from each finger. Finger rolled on paper after ink is

added to finger

Latent Prints

“Hidden” or “invisible prints”

Present forensic techniques allow investigators to view these prints.

Usually smudged, contain only part of the print, or are overlapped by another print.

Why is this a problem for investigators?

Patent Prints

“Obvious prints”

Left by transferring a certain material from the finger to a surface.

Photographed instead of being lifted from surface.

Plastic Prints

Prints left in a substance.

These are less common than any of the other types.

Examples include: Motor oil Candle wax

Chapter 3 Notebook Quiz

1) What are fingerprints? 2) What is the epidermis? 3) List 2 reasons the epidermis is

important. 4) List 3 reasons that fingerprints can be

left behind. 5) What is dactyloscopy? 6) List 1 unique property of fingerprints. 7) List and define the 4 types of

fingerprints.

Group Case Study # 2

1 paragraph to 1/2 page Should include 5 review questions Include the following terms:

Fingerprints Latent prints Exemplar prints Crime scene Questioned document

11/5/12 Journal 48:

On a separate sheet of paper, write and answer the following questions:

1) What is the difference between a solute and a solvent?

2) What are 2 reasons that the epidermis is important?

3) List and explain 4 types of fingerprints.

Case Study # 8

A body has been found in an abandoned car on the side of a busy interstate. The body has 3 gunshot wounds to the head. No witnesses have been reported and no gun was found. The car was reported stolen a week ago. A large amount of alcohol was found in the victim’s body. The only restaurant that serves alcohol in the area is 0.5 miles off the interstate. No alcohol or drugs were found in the car.

Case Study # 8 Review Questions

1) Where was the body found? 2) What is strange about where the

car was found? 3) How far is the closest bar? 4) If you were the lead investigator,

how would you conduct the investigation?

5) What evidence was found in the car?

Forensic Vocabulary

Demeanor: the way in which a person behaves

Battery: the unlawful striking of a person by another

Exhibit: to display Negligence: failure to act with care Charge:to make a claim or

wrongdoing against

Forensic Group Case Study # 3

Create a case study with a partner. Crime: burglary with fingerprint

evidence 1-2 pages Create an outline/brainstorm first

Forensic Group Case Study # 3

Outline all important ideas before beginning the story

Give enough details, but do not make the story too wordy.

Leave the audience in suspense. Make the reader have to think to figure out who committed the crime.

To do this, you have to include some background information.

Forensic Group Case Study # 3

Must include the following vocabulary: Demeanor Battery Exhibit Negligence Charge Patent prints Dactyloscopy Serology

Forensic Group Case Study # 3

This will count as a test grade: The following should be turned in:

Outline/Brainstorm (concept map) (15%)

1-2 page case study (50%) Detailed sketch of crime scene

(25%) 5-7 review questions (10%)

Case Study # 9

Ashlynn, a 3 year old girl, has just been reported missing. She was abducted from her home in Groveton, NJ. She and her mother had just returned from the grocery store. Her mother noticed her missing about 20 minutes later. All doors were locked and all windows were locked as well. Ashlynn is not old enough to open doors/windows by herself.

Case Study # 9 Review Questions

1) In a ½ page summary, tell me what you think happened. Include what steps you think investigators should take in order to find Ashlynn as well as how you think she was kidnapped. Include explanations for your scenarios as well as why you think it happened this way.

Notebook Quiz – 11/15

1) What is the difference between a solute and a solvent?

2) Define fingerprints. 3) List 2 reasons that the epidermis

is important. 4) What is dactyloscopy? 5) Why are fingerprints considered

unique?

Notebook Quiz – 11/15

6) Fingerprint I.D. is also called ___ 7) List and describe the 4 different

types of prints. 8) ______ _____ are known prints

collected from a suspect. 9) _______ ________ are hidden or

invisible prints. 10) _______ ______ are prints left in a

substance.

Chapter 3 Test ----- Monday 11/19

Know all vocabulary

Be able to define and tell the importance of the epidermis.

Know the 4 types of prints as well as examples of each.

Be prepared for a case study/essay question.