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South-Western / Cengage

Learning © 2012, 2009

DAY 1

Unit 1 Targets• Define observation and describe what

changes occur in the brain.

• Describe examples of factors influencing eyewitness accounts of events.

• Compare the reliability of eyewitness testimony to what actually happened.

• Relate observation skills to their use in forensic science.

• Practice and improve your own observation skills.

Unit 1 Targets• Determine the independent, dependent, and

controlled variables in sample scenarios.• Write hypotheses that includes prior knowledge in

their reasoning.• Take measurements using the metric system.• Convert units in the metric system

Quarter 1 Proficiencies• I can write/evaluate a hypothesis for an

investigation.

• I can design/evaluate a controlled, valid, and reproducible experiment.

• I can demonstrate that I make careful and detail observations through word descriptions, data, and drawings.

• I can evaluate/communicate if the data in an experiment support or refute the hypothesis.

Unit 1 Vocabulary

• analytical skills• control variables• deductive reasoning• dependent variable• eyewitness• fact• forensic

• hypothesis• independent

variable• logic• observation• opinion• perception

IntroductionIntroduction

The forensic examiner must be able to

1. find—identify the evidence

2. document—record the evidence

3. interpret—accurately determine the significance of the evidence

What Is Observation? What Is Observation?

Our brains can filter out information.

Point out some of the details in this photo.

What Is Observation? What Is Observation?

Our brains fill in gaps in our perception• In order to make sense of what we perceive,

our brains often enrich with detail what we see, taste, hear, smell, or feel

• After an event, we can believe things were part of the background even though they were not

What Is Observation? What Is Observation?

Our brains apply previous knowledgeto new situations

What assumptions can you make about this scene?

How might those assumptions be wrong?

What Is Observation? What Is Observation?

How information is processed in the brain

Learning to See Picture #1

Learning to See #1 Qs

• 1. At what location was the photograph taken? Glenville Municipal Center

• 2. How many cars are pictured? 2• 3. What color are the cars? Tan & gray• 4. What types of offices are located in the

building? Town, police and court offices• 5. How many small trees are in the picture?

2• 6. The photograph was taken New York State

during which season? Spring or summer• 7. How many people are in the photograph?

None

Learning to See Picture #2

Learning To See #2 Qs• 1. What is pictured in Photograph #2? Urn or pot• 2. Describe the shape of the object pictured?

Like a flowerpot• 3. What are the colors of the object? Red,

green, tan, blue, white brown• 4. What color edged the top of the object? Blue• 5. Upon what is the object displayed? A wooden

chair• 6. Describe or sketch the design on the object?

See above• 7. What is the approximate size of the object?

~12”-14” wide, ~ 16” tall

Learning To See Picture #3

Learning To See #3 Qs• 1. How many people are in Photograph #3?

One• 2. What is the sex of the person in the

picture? Female• 3. What is the approximate age of the person

in the photograph? 55• 4. What color is the person’s hair? Blonde

(dyed)• 5. Does the person have long hair or short

hair? Short• 6. Does the person have any distinguishing

features? Glasses? Yes

• 7. Can you describe the person’s clothing? • 8. Is the person wearing any jewelry? If so,

describe it. Gold necklace and earrings• 9. Can you describe where the picture was

taken? School room or office– 1.Based on evidence in the photograph, can you form

a hypothesis about the person’s occupation? Teacher

– 2. Is it possible to identify the interests of the person based upon evidence in the room?

Forensics and biology books imply this might be a science teacher.– 3. Do you think it is easier to answer questions about a

photograph if a person is in the picture? Yes because we can recognize familiar surroundings and situations.

Learning to See Discussion Qs

• 8. Did everyone answer the questions correctly?

• 9. If everyone viewed the same photograph, list some possible reasons why their answers differed.

Day 2

Observations by Witnesses Observations by Witnesses

Observations are affected by:

1.Their emotional states

2.Whether they were alone, part of a group, or near others

3.What type of and how much activity was going on around them

Eyewitness Accounts Eyewitness Accounts • Crime-scene reports often vary, due to:

– level of interest– stress– concentration– amount and kind of distractions present– prejudices– personal beliefs – motives– any lapse in time since the event

How to be a Good Observer How to be a Good Observer

Observe systematically

• Start at one part of a crime scene and run your eyes slowly over every space

• Look carefully at details of each piece of evidence

• Do not assume you will remember everything

How to be a Good Observer How to be a Good Observer

Turn off filters

• Consciously pay attention to all details

• Do not pay attention to just what you think is important

• All details are potentially important

How to be a Good Observer How to be a Good Observer

Collect Information first, interpret data later

• Look for patterns and make connections• More information yields better

interpretations• Prejudices exist everywhere—

– eyewitness accounts– your own thinking processes

How to be a Good Observer How to be a Good Observer

Documentation, Documentation,

Documentation

• Write down and photograph as much information as possible

• Be aware that memory is faulty• Remember that our brains tend to fill in gaps in our

perceptions

Identifying Variables

3 Kinds of Variables

• Independent Variable – something that is changed by the scientist– What is tested

– What is manipulated

3 Kinds of Variables

• Dependent Variable – something that might be affected by the change in the independent variable– What is observed

– What is measured

3 Kinds of Variables

• Controlled Variable – a variable that is not changed– Also called constants

– Allow for a “fair test”

For Example:

An investigation was done with an electromagnetic system made from a battery and wire wrapped around a nail. Different sizes of nails were used. The number of

paper clips the electromagnet could pick up was measured.

Independent variable:

• IV: Sizes of nails–These were changed by the

scientist

Dependent variable:

• DV: Number of paper clips picked up–The number of paper clips

observed and counted (measured)

Controlled variables:

• CV: Battery, wire, type of nail– None of these items were changed

White board practice in Groups of 2

The higher the temperature of water, the faster an egg will

boil.

• Independent variable – temperature of water

• Dependent variable – time to cook an egg

• Controlled variable – type of egg

White board practice #2

The temperature of water was measured at different depths

of a pond.

• Independent variable – depth of the water

• Dependent variable – temperature

• Controlled variable – pond, location

Day 5

The Innocence Project The Innocence Project • Barry C. Scheck and Peter J. Neufeld

Benjamin N. Cardozo School of Law, • Beginning in 1992, used DNA to

examine post-conviction cases• Faulty eyewitness identifications

accounted for up to 87% of the wrongful convictions

. . . . . . . . . . . . . . . . . . . . . . . . . . . . SummarySummary . . . .. . . .

• The environment and our natural sensory filters affect our ability to observe

• Eyewitness reports can be correct, faulty, or a little of both

• Acquiring good observation skills takes practice and training

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SummarySummary

• Forensic scientists:– Find and Document Evidence– Evaluate and Interpret– Provide expert testimony to courts

Metric System UnitsQuantity Base Unit Symbol

Length

Mass

Time

Volume

meter

gram

second

liter

m

g

s

L

Prefix Conversions

1. Find the difference between the

exponents of the two prefixes.

2. Move the decimal that many places.

To the leftor right?

Metric Staircase

532 m = _______ km0.532

A. SI Prefix Conversions

1) 20 cm = ______________ m

2) 0.032 L = ______________ mL

3) 805 dm = ______________ km

0.2

0.0805

32

Odd units1mL = 1 cm3

Data Types

• Quantitative- data measured with a number value (ex. 32 cm)

• Qualitative- data measured with your senses (ex. dim vs bright)

Hypothesis Writing

Format:

When the Independent (manipulated) Variable is increased/decreased (pick one), then the Dependent (responding) Variable should increase/decrease (pick one). This is because explanation.