1

Name: __________________________________ Homeroom: ________

Evidence of Activity Part A

Evidence & Investigation

2

Student Learning Expectations

Outcome I CAN apply observation and inference skills to recognize and interpret patters and to distinguish a specific pattern from a group of similar patterns by:

Checking for Understanding

recognizing evidence of recent human activity, and recognizing evidence of animal activity in a natural outdoor setting.

observing a set of footprints, and infer the direction of travel.

recognizing that evidence found at the scene of an activity may have unique characteristics that allow an investigator to make inferences about the participants and the nature of the activity, and give examples of how specific evidence may be used.

Use the picture above to answer the following question

Explain what you think might have happened? Which clues might the police use to help them investigate the crime scene and find the robber? ________________________________________________________________________________________________________________________________ ________________________________________________________________________________________________________________________________ ________________________________________________________________________________________________________________________________ ________________________________________________________________

Can you observe facts? Picture Edition You have one minute to observe the pictures. Then you can record them here:

3

How many objects were you able to list in pictures?

Can you observe facts? Words Edition You have one minute to observe the words. Then you can record them here:

How many objects were you able to list in words?

Crime Scene Observations 1. What was the better form of observation for you? 2. What can help you be a better observer? 3. What do you think makes a good observation?

Elementary, My Dear Watson Using Observation and Creative Thinking to Investigate Crimes

4

Everyone loves a good mystery. Mysteries can take us out of ourselves and lead us to explore the far reaches of our imaginations. Mysteries don’t just happen in books, on TV and in the movies. Unfortunately, crimes like robbery, kidnapping and others happen in real life too. A crime is any act that is against the law. We continually hear about crimes in the news. When we find out about a crime, we often wonder: “Who did it?” “How did it happen?” “Do we have any proof?” You may be surprised to learn that science often provides the answers to these and other questions. Forensic Science is the study of objects that relate to a crime. These objects related to a crime are called evidence. Forensic scientists study evidence so that it can be used as proof in court. The term forensic means “suitable for a court of law”.

When analyzing evidence, forensic scientists perform the same activities that scientists do: they observe, classify, compare, use numbers, measure, predict, interpret data, and draw inferences, or reasonable conclusions based on evidence. Forensic science is active and restless. It leaves no stone unturned. Forensic scientists can be police officers or detectives, special police officers responsible for investigating serious crimes. They can also be members of a city, regional or provincial forensic laboratory and work along with detectives and the police. Some forensic scientists have a background in criminology, the study of crime. Others specialize in the area of pathology (the study of the causes of death and disease), chemistry, biology, dentistry, psychiatry, psychology, or engineering. Large police departments have their own forensic scientists. In smaller police departments, the police officers often serve as both forensic scientists and investigators. Many areas have regional forensic laboratories that work with all local police departments. The “Ident Team” in Lethbridge works with our local police department. Most forensic scientists have university degrees in either criminology or a specialized field. A forensic scientist may also work in a university’s biology, chemistry, anthropology, or criminology department and be called to work with the police department when needed. At the scene of the crime, a detective takes notes, interviews witnesses, and sometimes collects evidence. The evidence is then sent to the forensic laboratory, also called the crime lab, to be analyzed. The forensic scientists use their skills in classification, comparison, observation and reconstruction to examine the evidence. They sometimes work “blind” meaning they don’t know other details about the crime. The results of their work reveal more about the crime and are given back to the detective. This evidence is added to the information gathered from the interviews. The detective, working with the forensic scientists, is then responsible for making an inference based on the evidence and solving the crime. The power of observation is the best tool that a detective and a forensic scientist have. To observe is to note carefully, paying attention to details. When a detective collects data at a crime scene, observations are very important. Observations include everything from the

5

objects found at the scene of the crime and statements from witnesses, to the time of day the crime took place and the temperature of the room where it occurred. A detective looks for clues, which are real measureable and countable observations of the crime and crime scene.

A detective does not know what data or evidence will eventually prove to be important, so he/ she observes everything. At the scene of the crime, the detective and forensic scientist work together to make sure all possible evidence is collected for later examination. If the evidence is badly handled, wrongly labelled, or allowed to become contaminated, it will be useless in the laboratory and the courts. Worse, if clues are

overlooked, the detective will get no second chance. There are four categories of evidence. Evidence that cannot be contradicted and directly ties a suspect to a crime is called conclusive/ individualized evidence. Circumstantial/ Class evidence on the other hand, is a piece of evidence that does not directly tie a suspect to a crime. Sometimes it allows the forensic scientist or detective to infer, deduce or assume if one piece of evidence is true/ false, then there may be other pieces of evidence that will also prove true/ false, eventually leading to a suspect. When one piece of circumstantial evidence leads to another piece of evidence this is known as corroborative evidence. Lastly, the evidence gleamed from witness testimony is called opinion evidence. It is important to note, witnesses are not to testify to their opinion of facts only what they know to be factual. In addition to making observations and gathering clues, a detective conducts interviews. He/ she may also tail, or security follow a person the detective thinks could be guilty of a crime, called a suspect. The detective uses this information, along with the evidence from the crime lab, to form a hypothesis, or an educated guess, about how the crime was committed and who did it. Detectives, like scientists, always keep an open mind (willing to accept new or different data, clues, and ideas) during an investigation and look for hypotheses that could explain the crime.

After reading “Elementary, My Dear Watson”, please answer the following questions. Answers must be complete sentences.

6

1. What is the best tool that a scientist can have? ________________________________________________________________________________________________________________________________ 2. Why is observation important to a scientist? ________________________________________________________________________________________________________________________________ 3. What are the consequences if evidence is not collected or taken care of properly? ________________________________________________________________________________________________________________________________ 4. What is it important for a scientist to keep an open mind? ________________________________________________________________________________________________________________________________ 5. At the scene of a crime, what might be some of the detectives’ activities? ________________________________________________________________________________________________________________________________ 6. Once the evidence is collected, where is it sent? ________________________________________________________________________________________________________________________________ 7. What are eight activities that all scientists perform? ________________________________________________________________________________________________________________________________ 8. What does it mean for scientists to “work blind”? ________________________________________________________________________________________________________________________________ 9. What are some of the skills scientists use to examine the evidence? ________________________________________________________________________________________________________________________________

Vocabulary

a. evidence:___________________________________________________

7

____________________________________________________________________________

b. inference: _________________________________ ________________________________________________________________________

c. observe: ___________________________________________________

__________________________________________________________________________

d. clues: _____________________________________________________

__________________________________________________________________________

e. hypothesis: _________________________________________________

__________________________________________________________________________

f. criminology: ________________________________________________

__________________________________________________________________________

g. constant variable: _____________________________________________

__________________________________________________________________________

h. manipulated variable: __________________________________________

__________________________________________________________________________

i. responding variable: ___________________________________________

__________________________________________________________________________

What Characteristics?

8

Look around at your classmates and carefully observe each person. Look for way to distinguish between them. A few examples could include: ________________, ______________ or _________________. What else could be used?

Let’s get specific! Physical Characteristics: are the observable traits of an individual such as their height, weight, color of skin, hair and eyes, shape and spacing of facial features, etc. We can use all or some of these to help distinguish one person from another. Use the Art of Crime Detection Web Quest to determine the major features of a face a Forensic Artist would look for in order to create a composite sketch of a suspect. List those features below: Thinking like a forensic artist:

• Were you able to successfully complete your assignment?

• Which one(s) were successful? Why or why not?

• What skills would you need to be more successful?

• Based on your experiences, is a single observation a reliable piece of

evidence?

• Would your teacher agree? Why do you think this? Take Your Measure

PROBLEM: Is there a correlation between shoe size and height?

9

(What is the question that we want to answer in performing this lab?) What does correlation mean? ___________________________________________ ________________________________________________________________ HYPOTHESIS: (An educated guess to answer your problem – complete sentence) ________________________________________________________________ ________________________________________________________________ MATERIALS: (List ALL the materials you need to complete the lab)

Ruler/ Meter Stick Graph Paper

PROCEDURE: (Step-by-step guide on how to complete the lab)

1. Predict what will happen to foot sizes as we compare to the height of classmates. 2. With a partner, measure one another’s height BARE FOOT, from heal to top of the

head. 3. With a partner, measure one another’s RIGHT foot length in cm as you are standing.

Record both of your data. 4. Once you have completed your own measurements, write your information on the

chart on the board. 5. Record the data for all classmates in your chart below. 6. Transfer the data from your chart into a graph. Create a histogram of the data on the

graph paper to display the results. OBSERVATIONS: (What you see when you are performing the lab –answers the question) Prediction Observation Inference (What do you think will happen?)

(What are your measurements? What are your partner’s measurements)

(What do you think will happen when you graph the class data?)

Your height (cm) Your foot length (cm) Partner height (cm) Partner foot length (cm)

Chart:

Height (cm) Foot Length (cm) Height (cm) Foot Length (cm)

10

11

CONCLUSIONS: (What did you find out when you completed the lab? – Look back to your problem, use complete sentences.)

12

________________________________________________________________

________________________________________________________________

________________________________________________________________

_______________________________________________________________.

QUESTIONS: (Answer each question in a complete sentence! CAPITALS AND PERIODS!!!) 1. Name 5 controlled variables in this experiment that we had to keep the same in order to compare the class results? ________________________________________________________________

________________________________________________________________

________________________________________________________________

2. What is the manipulated variable that we changed in this experiment? ________________________________________________________________

_______________________________________________________________.

3. What is the responding variable (what did we see) as a result of the change in the manipulated variable? ________________________________________________________________

_______________________________________________________________.

4. Do you think that the results would be the same for adults as it would be for grade 6’s? Why or why not? ________________________________________________________________

_______________________________________________________________.

5. Why did we measure the foot size in cm and not with the size of the shoe? ________________________________________________________________

_______________________________________________________________.

13

What do footprints tell you?

A footprint can tell us more than the type of shoe a person was wearing at the time the footprint was made. The ________ and ________ of the print allows investigators to estimate the height and gender of the person. The __________ of the print gives information about the person’s weight. The __________________________ prints gives information about the speed the person was walking or running. The ___________________________ of the print can even give us information about when it was made and the direction the person was travelling. Determining the brand of the shoe can help determine _________ spent on the shoe.

Tall people usually have bigger feet than short people.

Tall people usually take longer strides (steps) than short people.

People moving quickly usually take longer strides (steps further apart).

People running usually make deep toe marks (from pushing off the ground) or deep heel marks (from landing heavily).

14

Which Shoe? One day in January, Detective Barnes was called to the scene of a burglary. The owner of Rugged Rockies Outdoor Sports Store reported that a thief had broken into the store and taken mountain climbing gear, camping equipment and some sleeping bags. Detective Barnes checked the outside of the building, and in the snow under a broken back window he found a coil of rope. He thought that the thief was in a hurry and dropped the rope so Detective Barnes checked the snow for footprints. He found the three different prints you see on the following pages. Make your observations and answer the questions. Print #1 1. Write a minimum of 4 observations for the print.

___________________________________________________ ___________________________________________________ ___________________________________________________ ___________________________________________________ 2. What type of shoe do you think made the print? ___________________________________________________ 3. What could you infer about the shoe which made the print and the person wearing it? ___________________________________________________ ___________________________________________________ ___________________________________________________ ___________________________________________________

Print #2 4. Write a minimum of 4 observations for the print.

___________________________________________________ ___________________________________________________ ___________________________________________________ ___________________________________________________ 5. What type of shoe do you think made the print? ___________________________________________________ 6. What could you infer about the shoe which made the print and the person wearing it? ___________________________________________________ ___________________________________________________ ___________________________________________________ ___________________________________________________

15

Print #3 7. Write a minimum of 4 observations for the print.

___________________________________________________ ___________________________________________________ ___________________________________________________ ___________________________________________________ 8. What type of shoe do you think made the print? ___________________________________________________ 9. What could you infer about the shoe which made the print and the person wearing it? ___________________________________________________ ___________________________________________________ ___________________________________________________ ___________________________________________________

10. After analyzing these three prints, can Detective Barnes identify a suspect? Why or why not? Explain your reasoning. ________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

11. What other evidence should Detective Barnes look for? Explain. ________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

16

How are shoe size and height related? The graph below was created by four grade six students. They each measured the length of their longest foot and their height in centimeters (cm). Look carefully at the information in the graph and use it to help you answer the true or false questions on the next page.

Can the length of a person’s foot give you an idea of how tall they are?

17

Based on the information in the graph on the previous page. Read each of the following statements and put T beside the ones you think are True and F beside the ones you think are False. 1.______ People with longer feet are always taller than people with shorter feet. 2.______ People with longer feet are usually taller than people with shorter feet. 3.______The graph lists foot length on the x-axis. 4.______The graph lists foot length on the y-axis. 5.______Sue and Jenny are the same height but have different-sized feet. 6.______Tony is the tallest but has the smallest feet. 7.______Dan is the shortest and has the smallest feet. 8. Measure your height and length of your longest foot in centimeters (cm) and mark your measurements on the graph on the previous page. Write your name beside your point on the graph. What do the footprints below tell you?

_________________________________

_________________________________

_________________________________

_________________________________

_________________________________

_________________________________

_________________________________

_________________________________

_________________________________

18

Stride Types

Answer each of the following questions- Circle the correct answer.

Depth of Prints: Which is the deeper print?

a.) Walking b.) Running Depth of Prints: Which is the deepest print?

a.) Walking b.) Running c.) Carrying Object Clarity of Prints: Which is the clearest print?

a.) Walking b.) Running c.) Carrying Object Draw a diagram of the footprints a person would make when he/she was:

Walking

Running

Hopping or Jumping

Skipping

Based on what you have observed how could you infer that a person was running or walking by looking at the tracks left in the soil? ________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

Name of Student Length of walking stride

Length of running stride

Length of stride when carrying a

heavy object

19

Footprint Questions 1. The footprints are ___________________ when the soil is dry.

a.) clearer b.) about the same c.) not as clear

2. When the soil is wet the prints are ___________________. a.) clearer b.) about the same c.) not as clear 3. When a person is running, the length of his/her stride ________ as compared to the length of a stride when the person is walking. a.) is shorter b.) is greater c.) is about the same 4. The prints made while running are ________ than when the person is walking. a.) deeper b.) more shallow c.) about the same 5. The prints made when a person is walking are __________ than when the person is running. a.) about the same b.) clearer and more uniform c.) not as clear nor as distinct 6. When a person is carrying a heavy object the prints made are __________. a.) not as deep b.) deeper c.) about the same 7. A taller person’s length of stride when walking is ________ than a shorter person’s length of stride. a.) longer b.) shorter c.) about the same 8. Animal or human prints would be easier to see if the ground was _______. a.) dry b.) wet

20

What do Animal Tracks tell you?

Just as a footprint can reveal a lot about who made the imprint, animal tracks can tell you a lot about the animal that made the track. Read about the animals below and then match the most likely animal with each set of tracks by writing the name of the animal on the first line for inference.

A coyote walks on four large

paws that each have one large

pad and four smaller pads with

thick claws.

A mouse walks on four

very tiny feet with

sharp claws. Their

front feet have four

“toes” and their back

feet have five.

A squirrel walks on

four small feet that

look like bony hands

with sharp claws.

A rabbit hops on four

feet. The front feet

are much smaller than

the back feet.

A magpie walks on two

feet with three long

toes with sharp claws

at the ends.

A deer walks on four

legs leaving a split

hoof print which looks

like a mirrored tear

drop followed by two

small dots.

21

I can observe a set of footprints, and infer the direction of travel. Use the tracks below to make observations about the animal that left it. After you have made 2 – 3 observations for each track, use the information to infer which animal left the track, their speed and direction of travel.

Observations:

1.

2.

3.

Inference:

Animal: ____________________ Speed: _____________________ Direction: ___________________

Observations:

1.

2.

3.

Inference:

Animal: ____________________ Speed: _____________________ Direction: ___________________

22

Observations:

1.

2.

3.

Inference:

Animal: ____________________ Speed: _____________________ Direction: ___________________

Observations:

1.

2.

3.

Inference:

Animal: ____________________ Speed: _____________________ Direction: ___________________

23

Observations:

1.

2.

3.

Inference:

Animal: ____________________ Speed: _____________________ Direction: ___________________

Observations:

1.

2.

3.

Inference:

Animal: ____________________ Speed: _____________________ Direction: ___________________

24

I can recognize evidence of recent human activity, and recognize evidence of animal activity in a natural outdoor setting.

Study the diagram below of a forest clearing, then answer the questions below.

1. How many creatures have left prints? 2. List the type of creatures who have left prints. _______________________________________________________

_______________________________________________________

_______________________________________________________

_______________________________________________________

3. Describe the movements of each creature by its footprints. Make sure to use map directions in your description. ________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

25

4. Using inference, tell what could be happening to or with each of the creatures. ________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

5. Is there evidence of other human activity in the clearing? Explain how you know. ________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

26

Matching Activity How many pairs can you find?

Number Name Number Name ______ _______________ ______ _______________ ______ _______________ ______ _______________ ______ _______________ ______ _______________ ______ _______________ ______ _______________ ______ _______________ ______ _______________ ______ _______________ ______ _______________ ______ _______________ ______ _______________ ______ _______________ ______ _______________ ______ _______________ ______ _______________ Evidence:_________________________________________________________

Circumstantial or ___________ Evidence:_________________________________

________________________________________________________________

Conclusive or ___________ Evidence:____________________________________

________________________________________________________________

Which type of evidence will prove beyond any doubt that the suspect was at the crime scene?

a.) Class Evidence c.) Individual Evidence b.) Conclusive Evidence d.) Circumstantial Evidence

A smoldering campfire shows that someone was at the campsite, but doesn’t tell specifically who? This is an example of: (Choose two)

a.) Class Evidence c.) Individual Evidence b.) Conclusive Evidence d.) Circumstantial Evidence

A shoe print that has a nick or scratch in the tread is an example of:

a.) Conclusive Evidence b.) Circumstantial Evidence

A clear shoe print found in the dirt at the scene of the crime is an example of

a.) Conclusive Evidence b.) Circumstantial Evidence Which kind of evidence is the most powerful? ____________________or ____________________ evidence The scratch marks left on bullets as they leave the bore of a specific gun is an example of:

a.) Class Evidence c.) Individual Evidence b.) Conclusive Evidence d.) Circumstantial Evidence

27

Crime Scene Analysis Part B

Student Learning Expectations

Outcome I CAN apply knowledge of the properties and interactions of materials to the investigation and identification of a material sample by:

Checking for Understanding

investigating evidence and link it to a possible source, e.g. by: • Classifying footprints, tire prints and soil samples • Analyzing ink from different pens • Analyzing handwriting samples • Comparing fabric samples • Classifying fingerprints

Tire Treads and Impressions Characteristics

________________________ and _______________________ are used to identify the type of tire and perhaps the make and model of the vehicle. The nature of the impression determine how the vehicle was driven.

The Anatomy of a Tire The tire’s tread is divided into ridges (elevated areas) and grooves (indented areas)

• Tread patterns are symmetrical • Ridges (ribs) and grooves are counted across • Unique characteristics are noted (imperfections, pebble

embedded in the grooves, etc) • Tire impressions are made (paint tire, drive over

smooth surface) To Identify the Vehicle Investigators will measure the:

• Track Width - center of each tire to the center of the opposite tire

Ridge

Groove

28

Making Tracks PROBLEM: What inferences can you make from a tire tread? (What is the question that we want to answer in performing this lab?) HYPOTHESIS: (An educated guess to answer your problem – complete sentence)

_______________________________________________________ _______________________________________________________ MATERIALS: (List ALL the materials you need to complete the lab)

Tires Wax crayons/ pencils Paper – Legal x 2 pieces Paper – Letter x 2 pieces

PROCEDURE: (Step-by-step guide on how to complete the lab)

1. In pairs, examine tires in the parking lot, looking for differences in the tread patterns (spacing, depth, shape and design), and evidence of wear, size and possible damage to the tire surface.

2. Select a tire, place the paper on an area of the tire, and make a rubbing using the legal size paper.

3. Repeat procedure with another tire tread. 4. In pairs, examine bike tires on the bike rack, looking for differences in the tread

patterns (spacing, depth, shape and design), and evidence of wear, size and possible damage to the tire surface.

5. Select a tire, place the paper on an area of the tire, and make a rubbing using the letter size paper.

6. Repeat procedure with another bike tire tread. 7. Record observations in your chart. 8. Name at least two observations about the various tire tracks collected. From your

observations, make an inference about what the vehicle has been doing.

Not all tire tracks are the same. Tires come in different sizes and widths. Tire tread patterns are also different. Different manufacturers make tires. Usually tires made by the same manufacturer will have similar tread patterns because they are made on the same machine. Tires found on trucks are very different from tires found on bikes. Tire tracks are important in solving crimes because they can prove if a vehicle was at a scene of a crime.

29

OBSERVATIONS: (What you see when you are performing the lab –answers the question) Tire Treads Tire Observations & Distinguishing

Characteristics Inference

(2 Vehicle tires, 2 bike tires) Spacing, depth, shape and design, evidence of wear, size and damage

(What do you think the vehicle or bike has been doing?)

Vehicle Tread 1

Vehicle Tread 2

Bike Tread 1

Bike Tread 2

CONCLUSIONS: (What did you find out when you completed the lab? – Look back to your problem, use complete sentences.) _______________________________________________________

_______________________________________________________

_______________________________________________________

_______________________________________________________

_______________________________________________________

30

QUESTIONS: (Answer each question in a complete sentence! CAPITALS AND PERIODS!!!)

1. Are all tires the same (bikes vs. vehicles)? Explain. ___________________________________________________ ___________________________________________________

2. Do different manufacturers have the same tread? Explain.

___________________________________________________ ___________________________________________________

3. Do all vehicles have the same tires (cars vs. vans, trucks vs. cars, etc)? Explain. ___________________________________________________ ___________________________________________________ ___________________________________________________ ___________________________________________________

4. What are some things you might be able to infer from a tire track? Explain. ___________________________________________________ ___________________________________________________ ___________________________________________________ ___________________________________________________

31

Dust, Dirt & Soil Dust, dirt and soil can be important evidence in an investigation. Try the following activity to see how dirt can be used to solve a crime. 1. Collect dirt from different locations. Place it in the plastic bags and mark the locations on each bag. 2. Place the dirt sample from each bag on separate sheets of white paper. Examine the samples with the magnifying lens. a) How are the dirt samples different?

b) Describe the size of the grains in the soil.

c) Do you see any stones?

d) Is there any decaying plant material in the soil? e) What characteristics could you use to identify the dirt from a particular place?

What does the colour of soil tell you?

• Indicates the material that makes up the soil • Soil rich in humus will be dark in colour • Soil from an unpaved parking lot may contain very little humus and lots of sand and

pebbles to keep the water from collecting there • Other materials found in soil may include: insect parts, fur, hair, bones, branches,

other plant material, etc. Soil Terms

• Porosity - is how much liquid the soil will hold. • pH Is the soil’s acidity (is the soil an acid or a base?) • Texture:

o The grittiness of soil can be tested by wetting a small amount of the soil and rubbing it between your thumb and two fingers.

• Soil made up of very small particles will feel smooth • Soil containing sand or larger, coarser particles will feel rougher and gritty

Soil is one-half air and water, both of which are necessary for plants and animals to live. The rest of soil consists of recycling organisms – such as fungi, molds, bacteria, and earthworms – pieces of rock and humus (decaying plant and animal matter). The size of the soil particles determines whether soil is sand, silt, or clay. Sand has the largest soil particles and clay has the smallest.

32

All this information can be used to study soil samples found at a crime scene. Police compare soil samples found at the scene of the crime with those found on suspects clothing, shoes or in their car. Dust and dirt are common as trace evidence because they are easily carried from the scene of a crime in the soles of shoes, on clothing, or on the tires of a vehicle. Forensic scientists compare the dust and dirt found at the crime scene with selected samples to determine where they came from.

Soil Comparison

Soil

Sample Colour Texture Odour Content Particle Size

# The colour of the soil

How soft, course, smooth, gritty the soil feels

How the soil smells

Can the different sizes be separated? Which type of soil is heavier?

How big/ small one piece/ particle is

1

2

3

4

5

6

33

Handwriting Analysis/ Graphology Forensic investigators who compare handwriting are known as forensic document examiners. Document examiners look at differences found in handwriting and printing to look for forgeries. Some of the indicators used in comparing handwriting samples are:

• _______________________ and slant of the letters

• Spacing of the __________________

• Pressure on the ________________________

• Formation of the __________________ in letters such as L, O, f, p, B, etc.

• _______________________ of the letters i, j

• _______________________ of the letter t

• How letters are ________________________________________

• How words end - ______________________________________

• A ___________________________ of printing and writing

• Formation of less common letters (y, x, q, z, etc)

• _________________ of words and letters

• ___________________________________ on the page

• Writing __________________ used

Things to look for in forgeries • Stopping in the middle of writing the name

• Heavier pen flow

• Slant of writing

• Pencil marks underneath

• The spacing of the letters

• The loop in the l, a, and e

• The formation of the letter s

• The crossing of the t and the dotting of the

i, j

34

Graphology Comparisons 1. Compare the writing samples in your group. List three similarities and differences your group finds below. A. The similarities are: B. The differences are: 1. 1.

2. 2.

3. 3.

2. Which two characteristics were the most helpful in helping you tell the difference between various handwriting samples?

A. _________________________________________________________

___________________________________________________________

B. _________________________________________________________

___________________________________________________________

3. Use handwriting to write your name on the following 4 lines. _______________________________ _______________________________ _______________________________ _______________________________ 4. Is your signature the same each time? Why or why not? ________________________________________________________________

________________________________________________________________

5. Use printing to write your name on the following line. _______________________________ 6. Compare your printed name to your handwritten name. If we did the same activity with paragraph #1 handwritten, but changed paragraph #2 to printing, could you identify each person who wrote the samples? ________________ 7. Explain why you think you will/ will not be able to identify each person who wrote the samples. What factors would change? ________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

35

Handwriting Detectives Detectives at the scene of the kidnapping of the Central School mascot found a hastily-written note. Acting upon tips from students, four suspects were detained, and brief hand-written samples taken from each.

36

Handwriting Detectives Continued Making use of the factors used by graphologists to analyze handwriting (loops, spacing, etc.) decide which suspect you believe wrote the ransom note by comparing each sample to the note. Record your observations in the chart.

Loops Spacing End Strokes

1 and Note

2 and Note

3 and Note

4 and Note

Which suspect wrote the ransom note? Suspect # __________ wrote the ransom note.

Explain how you reached this conclusion.

________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

37

Paper Chromatography Chromatography is an important way of separating mixtures and solutions. There are different methods of Chromatography, but in all of them, substances are separated as they move at different speeds and involves using a solvent. Paper chromatography is a method for separating pigments (colours) in mixtures such as ink. PROBLEM: How can you match an ink sample with the pen that it came from? (What is the question that we want to answer in performing this lab?) HYPOTHESIS: (An educated guess to answer your problem – complete sentence) ________________________________________________________________ ________________________________________________________________ MATERIALS: (List ALL the materials you need to complete the lab) Chromatography paper Water Markers ________ are permanent black ink ________ non permanent black ink ________ non permanent coloured ink PROCEDURE: (Step-by-step guide on how to complete the lab)

1. Label the beakers marker A, B, C, D, E, F 2. Working in a group, students draw a line approximately

1 cm from the bottom of a strip of chromatography paper, using Marker A. 3. Repeat step 2 with markers B, C, D, E, and F. 4. Suspend the chromatography paper into the labeled beakers, so the bottom edge is

within 1 inch of the bottom of the beaker. 5. Pour water into a beaker until it reaches the bottom edge of the paper. 6. Observe what happens to the paper in the water and the pigment from the pen. Record

observations in observation chart. 7. Remove the strip before the water reaches about ¾ way to the top (about 5-10 min.) 8. Take the chromatography paper out of the cup and let the strip dry. 9. Observe what happens to the paper in the water and the pigment from the pen. 10. Any markers in which the ink was insoluble (did not separate). Complete previous

procedure using acetone. Definitions: Controlled Variables (What did you keep the same?): ________________________________________________________________________________________________________________________________ Manipulated Variables (What did you change?): ________________________________________________________________________________________________________________________________ Responding Variables (What happened because of the change): ________________________________________________________________________________________________________________________________

38

OBSERVATIONS: (What you see when you are performing the lab –answers the question)

Pen 1 Pen 2 Pen 3 Pen 4 Pen 5

Test Strip

Observations

CONCLUSIONS: (What did you find out when you completed the lab? – Look back to your problem, use complete sentences.) Inks that are insoluble are not water soluble. Inks that are soluble are water soluble. The solvent in this experiment was water and the solute was the inks. Inks ran up the chromatography paper are (non-permanent) soluble in water. Inks that did not run are insoluble (permanent) in water. This means that they will not dissolve in water but these inks may dissolve in another solvent like acetone or alcohol. Define the following words a) solute _______________________________________________________ _______________________________________________________ b) solvent _______________________________________________________ _______________________________________________________ c) dissolve ______________________________________________________ _______________________________________________________ d) soluble _______________________________________________________ _______________________________________________________ e) insoluble _____________________________________________________ _______________________________________________________

39

QUESTIONS: (Answer each question in a complete sentence! CAPITALS AND PERIODS!!!) Which black markers separated? _______________________________________________________ _______________________________________________________ Did they all separate the same? Explain. _______________________________________________________ _______________________________________________________ _______________________________________________________ _______________________________________________________ Which black markers did not separate? ______________________________________________________________________________________________________________ _______________________________________________________ _______________________________________________________ Give one reason why some of the markers did not separate? _______________________________________________________ _______________________________________________________ _______________________________________________________ _______________________________________________________ Explain why the markers that did not separate in water were tested again, the second time using acetone as the solvent? _______________________________________________________ _______________________________________________________ _______________________________________________________ _______________________________________________________ _______________________________________________________ How could chromatography help solve a crime? _______________________________________________________ _______________________________________________________ _______________________________________________________

40

Fabrics

Natural fibers such as flax, cotton, wool, silk and linen have been used for thousands of years to make various styles of clothing. On the other hand, man-made fibers are relatively new, dating back about a hundred years. Man-made fibers do not occur naturally. There are four main manufactured fibers - rayon, acetate, triacetate and lyocell. Synthetic fibers are produced from chemicals made from refined petroleum and natural gas. The main synthetic fibers are polyester, nylon, acrylic, polyolefin and spandex. Both natural and man-made fibers have their advantages and disadvantages. Natural fabrics are absorbent and comfortable to wear, but they shrink and wrinkle easily. Man-made fibers, on the other hand, are durable and easy to care for, but they aren't as absorbent and comfortable to wear. However, the blending of fibers, and technological advancements has blurred these lines of distinction allowing for more customizable fabrics.

Day through night we are surrounded by fabrics, from clothes we wear to the sheets that keep us warm, to the umbrellas we use when it rains. Which fabric we use largely depends on its most suitable application, which depends on its properties such as absorbency or flammability. Absorbency is a way to describe how much liquid the fabric can hold in its fibers. The fabric we use is actually a network of very thin threads, or fibers that are twisted together. The shape of this fiber determine the absorbency of the fabric. Flammability is a way to describe how quickly a piece of fabric can burn if caught on fire. The weave and weight of the fabric will affect how readily it will ignite and burn. Untreated fabrics such as cotton, silk or linen will burn more easily than wool.

3 ways fabric weaves can be made:

• Interlacing (woven fabrics)

• Interlooping (knitted fabrics)

• Bonding (non-woven fabrics)

41

Textile Fibers

42

Fabric Forensics

Type of Fabric

Description Stretch Absorbency Wrinkling Flammability Thread

Denim (dark grey)

Organza (orange)

Silk (pink)

Cotton (light blue)

Rayon (green)

Nylon (Aqua)

Chiffon (grey)

Polyester (purple)

Fleece (green pattern)

43

Fingerprint Background Almost every time you touch something, you leave a fingerprint. Our hands are covered with sweat pores. Sweat is often mixed with other body oils and dirt and when you touch something with your fingers, the oils and dirt on your skin stick to the surface of the object leaving an imprint of your fingertips. Prints that you can see with the naked eye are called visible prints. Invisible prints are called latent prints. Most fingerprints are latent prints. A third type of print is a plastic print. It is a print that leaves an impression on objects such as soap or clay. A forensic scientist is interested in fingerprints as a means of identification to help solve crimes. Fingerprints have been used as a means of identification for centuries. In ancient Babylon, fingerprints were used on clay tablets for business transactions and in ancient China, thumb prints have been found on clay seals. Fingerprints offer an infallible means of personal identification. The outer layer of skin on our fingers is made up of a series of ridges. The ridges on each person's fingers are unique. Other personal characteristics change - fingerprints do not. Police agencies have collections of fingerprints that number in the millions. Investigators often compare fingerprints from a crime scene to the fingerprints in fingerprint banks to see if they can find a match and thus know who committed the crime. They often fingerprint suspects to see if their fingerprints match those found at the crime scene. There are three basic types of fingerprints - the arch, the whorl and the loop. Arch patterns have lines that start at one side of the print and then rise toward the center of the print and leave on the other side of the print. Whorl patterns have a lot of circles that do not leave either side of the print. Loop patterns have lines that start on one side of the print and then rise toward the center of the print and leave on the same side of the print they start on.

Fingerprints are the most reliable system of identification used today. Height, weight, hair colour, and appearance change over time. Fingerprints remain constant over a person’s lifetime. Although every person in the world has a unique set of fingerprints, all fingerprints can be classified as one of four main patterns: loop, whorl, arch and composite. There are variations on these patterns, such as a left loop, a right loop, a double loop, a mixed whorl, and a tented arch. Every finger has a different print, and usually even a different pattern of print. The more prints obtained, the more conclusive the identification can be.

44

Fingerprint Patterns

Arch: The lines in arches flow across your fingertip from one side to the other with an arch in the middle. This is a plain arch. A tented arch has a tent shape that sticks up in the middle (not common).

• Approximately 5% are arches

Loop: Loops are the most common type of fingerprint pattern. Loops that flow towards your little finger are called ulnar loops (most common), while loops that flow towards your thumb are called radial loops (least common).

• 60 - 70% are loops

Whorl: Plain whorls have spirals, ovals or circles in the center. There are three types: the central pocket whorl, double loop, or accidental whorl. A whorl patter has a lots of circles that do not leave either side of the print.

• 25–35% are whorls

Composite: A combination of two or more of the patterns below.

45

Finding my Prints

Comparing Print Patterns in Class

LEFT HAND

Arch: ________________

Loop: _______________

Whorl: _______________

Composite: ___________

RIGHT HAND Arch: ________________

Loop: _______________

Whorl: _______________

Composite: ___________

46

Arch Loop Whorl Composite

Science Vocabulary Variable: A condition that affects the outcome of an experiment

47

Independent Variable or Manipulated Variable: A variable that is changed. Only one per experiment. Controlled Variable: The variables that stay the same every time an experiment is performed. Responding Variable or Dependent Variable: What you see happening in the experiment- the result. Fair Test: controlling the variables so you are only changing on variable in the test. Hypothesis: An educated guess about what you think will happen. Composition: Made up of. Vertical: Runs up and down. Horizontal: Runs left to right. Level with the horizon. Observation: What you see. Inference: What you can tell based on the observation. Conclusion: The end result. Example: Bob and Sam wanted to test how high different balls would bounce. They gathered 9 different balls and Sam dropped them each from 2 meters. They recorded how far they bounced back up on the first bounce.

Controlled Variables Manipulated Variable Responding Variable -All balls dropped from the same height (2m) -All balls measured the same way to record 1st bounce -All balls dropped by the same person (Sam)

-The type of ball (there were 9 different balls)

-How high they bounced

Evidence and Investigation Study Guide

How do police and investigators solve crimes? Observations are information gathered through our senses (see, smell, touch, taste, hear)

48

Inferences are a conclusion about something based on an observation. Example: Jim observed that there was a broken window in the classroom. The glass was on the inside of the classroom. Jim inferred that the window was broken from the outside of the classroom. Classify means to arrange things in groups according to similar qualities. Dichotomous keys are an easy way to help to identify things. Evidence is any bit of information, physical markings or objects that give people a reason to believe something. Common types of evidence are

-Fingerprints -Witness identification -Materials and fibers -Hand writing samples -Tire tracks -Soil samples -Animal tracks -Shoeprints or footprints

Fingerprints are a mark left by the tiny ridges of your finger tip. These markings are left by dust or other particles on the oil of your skin. There are 4 main types of fingerprints:

-The Arch fingerprint goes from one side of the finger to the other -The Whorl fingerprint has a central circle area with ridges circling around it. The whorl ridges do not go from one side to the other. -The Loop fingerprint begins at one side of the finer, loops around and the ridge ends at the same side of the finger that it began. -The Composite fingerprint is a combination of the whorl, arch or loop together on the finger

Within the fingerprint, there are characteristics that help investigators match up fingerprints. These are ridge characteristics. These might include:

- Forks (bifurcation): here 1 ridge splits to form 2 ridges - A Island: a short ridge is by itself and not attached to any other ridges -A Ridge Ending: where a ridge just ends

Fingerprints can be lifted off surfaces using powders, brushes and tape. Smooth surfaces are easier to lift prints off than rough surfaces. Some surfaces ar not good for lifting prints off of. Good Surfaces: glass, mirrors, smooth plastic, smooth metal Bad Surfaces: Bricks, materials, wood Fingerprints can only be matched if they have a suspect to compare samples to or if the suspect has fingerprints in the database. Shoeprints can be classified by size, pattern of the print, wear of the pattern. -Lots of tread on shoe -Differed tread on toes than on middle and back -Heavy tread on outside on heel and toe -Logo in middle of shoe -Right shoe

49

When trying to identify specific wear patterns, look for wear on the heel, on the toes, and wear on the treads. Looking at the Tread on a shoeprint can give investigators an idea of what type of shoe it is. Example: Hiking shoes- lots of deep tread - Dress shoe- no tread Looking at the direction of the shoeprints and the depth of the shoe prints can help investigators figure out which direction the person was going. Looking at the spacing between the shoeprints can tell investigators if the person was running (large space) or walking (smaller space).

Running Walking -Large space between prints -Deeper prints -Outline may not be as clear (dirt kicked up) -Line of prints are straighter-not as parallel

-Smaller spaces between prints -Shallower prints -Outline clearer -Less of a straight line- more parallel

Animal prints can also be identified based on the pattern left in the soil.

Tire Tracks can be classified based on -Type of tread -Wear of tread -Size of tread Fibers and Fabric can be classified based on

-Color -Flammability -Pattern of weave -Strength -Texture

Soil Samples can be classified based on -Color -Size of particles -pH -Make up (composition) -Smell Handwriting samples can be compared by looking at -The loops in the letters -The pressure on the page -The crosses on the t -A combination of writing and printing -The spaces between the letters and the words -The size of the letters -The slant of the letters -The dotting of letters (i,j) Investigators can also use chromatography to compare samples of ink by separating them into the colors that they are made up of.

Evidence & Investigation Word Search

Observation Inference -Hoofed animal -2 hooves on foot -4 feet same size

Deer

50