Capítulo 7: Plan de comunicación
7.7. Destinatarios de la comunicación de Grow Up
1. Set up one crime scene in your room that is always available for students to observe. You can use the same photocopied blood drops that you will give students (Page #1, #4, #10, and #11) OR you can print off more realistic red-colored blood drops - these can be found on the CD included with this book in the folder labeled “Blood Spatter For
Nashville Police Job”. Tape together the blood spatter pages and blank pages as shown in the student’s “Instructions For Constructing And Analyzing The Blood Spatter
Evidence” and tape to a wall in your room with the bottom placed 1 foot above the floor. Try to tape the blood spatter evidence pages in the middle of a wall (if you have room) so there is a 2 foot area of free space to the left (as you face the wall) and at least
5 feet of free space to the right (as you face the wall). DO NOT “string” this crime scene – it is only available for students to observe.
2. Each student group will also have to set up their own crime scene for analysis. They should first tape their blood spatter pages and blank pages together (following their instructions), then find a place they can hang the evidence on a wall. Each group will need about 10 feet of flat wall space that is at least 6 feet tall (we have students tape their crime scenes to the lockers in the hall outside our classrooms). Make sure each group has at least a 2 foot area of free space to the left of their evidence (as you face the wall) and at least a 5 feet area of free space to the right of the evidence (as you face the wall). They will need this space to locate the Points of Convergence (for instance, the evidence should not be placed near a corner.
3. Students will next use the string to create lines through the blood drops – finding the Points of Convergence.
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4. Near the end of class students will need to dismantle their crime scenes (unless you are lucky and have a protected area where they can remain up). Students can carefully remove their large crime scene from the wall (without tearing) and fold the pages up along their taped edges (it should fold up to a one page size). Students will need to remove strings from where they are taped to the wall, but SHOULD NOT remove the strings where they are taped next to blood drops on their papers. The strings can simply be folded up in the papers. The next day students should be able to quickly set up the crime scene again, pull their strings out, and tape the strings back in place on the wall for analysis. Students can also place tape around the strings where they intersect at a Point of Convergence to hold them together, which will make it easier to set up again. 5. Students will need to have their crime scene constructed on the wall to:
A. “string” the blood spatter and find the different Points of Convergence (there are THREE – see Key To The Crime)
B. Measure the distances from blood drops to Points of Convergence (so they can calculate how far away from the wall the victim was when hit – the Points of Origin).
C. Measure the height of each Point of Convergence from the ground (so they will know at what height the victim was hit each time).
D. Make a sketch of the crime scene to use in court.
Most students can build their crime scene and complete these measurements in two-50 minute class periods.
6. Students can complete the remaining measurements and calculations without constructing their crime scene:
A. measure the length and width of all blood drops to calculate Impact Angle. It is easiest if you have extra single sheets of the blood drops on Pages #1, #4, #10, and #11 that you give to students for them to measure.
B. calculating Points of Origin.
7. Students can always observe the crime scene you have constructed in your room if they need to OR they can tape their crime scene back on the wall for additional information.
How To Set Up and Complete Court:
1. This Job will be graded by having each group attend “court” as expert witnesses. You will play the part of both a prosecuting attorney and defense attorney asking the group members questions.
2. Print off copies of the “Teacher Script, Questions, and Scoring Guide For Blood Spatter Court Case” (this can be found following these Teacher Notes). You will need one scoring guide per group. This page contains an exact script for you to follow. Group members will be asked questions, and you will mark a grade on the form based on the answers that are given.
3. Decide where you want court to be held. To prevent groups from hearing each other we have court in the hall, just outside our rooms.
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4. Set up court by placing a table with chairs (or desks) for the group members to sit – you can stand or sit. You should have a copy of the crime scene blood spatter available (you will be asking group members to show you where the impacts/hits took place). You can either tape up and use the life-sized blood spatter crime scene (that you constructed to use in your room) OR you can use the “Courtroom Blood Spatter Evidence Page” that follows these Teacher Notes. If you use the life-sized blood spatter crime scene you should have students get up and show you locations as you ask them questions from the script. If you use the “Courtroom Blood Spatter Evidence Page” you would simply have students point to different areas of the page as you ask them questions from the script. 5. The “Teacher Script, Questions, and Scoring Guide For Blood Spatter Court Case” is easy to use. By rotating through the group as you ask questions (as stated in the scoring guide instructions) you can prevent a strong group member from dominating. However, make sure everyone in the group knows they have the right to make corrections or add to an answer after the initial response has been given (this is only fair since it is a group grade).
6. As stated in the scoring guide, the final questions from the defense attorney are
individual questions for individual grades. Each group member must attempt to answer their question without help from others.
7. This is a great opportunity for students to experience oral communication. Some students will be nervous – especially when they realize they will be under pressure to answer their own question.
8. Have fun playing your attorney parts!
Comments/Problems:
This Training Lab usually takes 4 - 5 days to complete. Day 1 – introduce crime, students tape together blood spatter pages, students begin stringing crime scene, begin taking measurements if time permits; Day 2 – finish stringing crime scene (if needed) or tape crime scene back up to take measurements, sketch crime scene, begin calculations to find Impact Angles, and Points of Convergence, begin organizing data; Day 3 – finish any calculations, organize data for court, analyze data to come to conclusions; Day 4 – you can begin court with those groups that are ready, while other groups finish organizing and analyzing; Day 5 – finish court with the remainder of your groups.
The strings students initially stretch out from the blood drops will rarely intersect perfectly to indicate Point of Convergence. A small error in lining up the string through a blood drop could easily result in a several inch error in string placement 4 feet away from the drop. Students will need to have patience and spend some time adjusting the strings to locate the exact points of intersection (Points of Convergence).
You should not expect each group to have the EXACT same calculated results. As stated in the previous comment – each group will likely have slight variations in their Point of Convergence locations, which will affect their calculations. However, each group should have SIMILAR calculated results – and come to the same conclusions concerning what happened on the day in question.
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You may want to set up an example on your chalkboard to show students how to use strings to find a Point of Convergence (draw three blood drops, tape strings, then adjust strings to find the exact point of intersection).
The blood drops found on the Blood Evidence Pages #1, #4, #10, and #11 were positioned perfectly on the pages so students could find Points of Convergence, and calculate Impact Angles and Points of Origin accurately. However, during the copying process a page may be twisted slightly or shifted a little to one side. This will result in the drops on that page being slightly out of position, however, this rarely results in a problem and students still manage to successfully solve this crime.
A page titled “Instructions For Constructing And Analyzing The Blood Spatter Evidence” has been included with this job. It is your choice to make it available for students or not. The “Instructions” page helps students become a little more organized as they work their way through the many measurements and calculation needed for this activity.
Students will feel like they are reconstructing a crime scene directly out of a C.S.I. episode.
Typical Results:
A Key to the Crime Scene (sketch of the blood spatter, Points of Convergence, Points of Origin, Heights of Impact, and probably sequence of events immediately follows these Teacher Notes.
Refer to Table 1- Table Of “Typical Measurements and Calculations” for a typical set of data and calculation results. Table 1 immediately follows these Teacher Notes.
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TEACHER SCRIPT, QUESTIONS, AND SCORING GUIDE FOR BLOOD SPATTER COURT CASE Instructions: Read the script below out loud while playing the roles of prosecuting and defense attorneys (text in italics is information for you only and should not be read out loud). Numbers to the left of each question tell you which witness should be asked that question. Other group members may add to an answer or change an answer only after the original person asked has had a chance to respond. Underlined questions are those that will be graded for a correct response. Grade as you go - check the star if the response is correct, circle the appropriate “minus” points for an incorrect response. Total Points for the group grade = 125 points. Points for the Individual Question grade = 30 Points. Have fun and play the parts!
I would like to call __________________ to the witness stand. (have the team come to court)
Please state your names for the record. (write down student names below)
Witness #1_________________________________________________ Witness #2_________________________________________________ Witness #3_________________________________________________
I am the prosecuting attorney in this trial against Brandon Coates, and I would like to ask your team some important questions that might help prove Mr. Coates’ guilt.
#1 - What is your profession?
#2 - Did you observe the crime scene at the home of David Short and Brandon Coates?
#3 - And what kind of evidence did you find at the crime scene?
#1 – How many total blood drops did you find at the crime scene? (9 drops)
#2 - Did you complete a thorough analysis of the blood evidence at the crime scene?
#3 - Do you have a copy of all the blood spatter evidence calculations you made during
your analysis? (collect the group’s Data Table or Tables at this time and grade it)
Table/Tables are neat, correctly labeled, and easy to understand and follow. Table displays all important data, including all blood drop lengths/widths, all blood drop Impact Angles, and all blood drop Points of Origin.
#1 - I see here that you calculated something called Impact Angle. Can you explain to
the court what an Impact Angle is? (the angle a blood drop hits a surface)
#2 - I also see that you calculated Point of Convergence. Can you explain to the court
what a Point of Convergence is? (the general location of the impact)
#3 - And I also see that you calculated Point of Origin. Can you explain to the court
what a Point of Origin is?(the exact location of the impact above convergence)
#1 - Can the calculations you just described help you analyze blood spatter evidence
and determine how many times a person may have been hit?
#2 - Brandon Coates claims he hit David Short one, single time. Based on your
calculations and analysis of the blood spatter evidence - do you agree with this statement? (NO)
#3 - Based on your calculations and analysis of the blood spatter evidence - how many
times do you believe David Short was hit? (THREE) (fill in the names)
/ -5 / -10 -5 / -15 -10 -5 / -10 -5 / -5 / -10 -5 / -10 -5 / -10 -5
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Here is a replica of the blood spatter found at the crime scene (show the team the actual sized blood spatter taped to the wall or the single page replica of blood spatter – see Teacher Notes for details )
#1 - Would you show the court where you believe David Short was located when he
was hit for the first time? (look at crime scene key – should be similar)
#1 - How far from the wall was David Short standing when this first
blow occurred? (about 2’ 5”, or 29”, or 73cm)
#1 - At what height did this first blow occur? (about 5’ 7” , or 67”, or 171cm)
#1 - An autopsy revealed that David Short’s injuries were found only on his head. Is
it possible that a blow at this height could have hit David Short in the head?
#2 - Would you show the court where you believe David Short was located when he
was hit for the second time? (look at crime scene key – should be similar)
#2 - How far from the wall was David Short standing when this second
blow occurred? (about 1’ 10” , or 22” , or 55cm)
#2 - At what height did this second blow occur? (about 4’ 9”, or 57“, or 143cm)
#2 - Is it possible that a blow at this height could have hit David Short in the head?
#3 - Would you show the court where you believe David Short was located when
he was hit for the third time? (look at crime scene key – should be similar)
#3 - How far from the wall was David Short standing when this third
blow occurred? (about 1’ 7”, or 19”, or 47cm)
#3 - At what height did this third blow occur? (about 10”, or 26cm)
#3 - This third blow to David Short’s head appears to be slightly above the ground.
In your opinion, what was the probable cause of this blow? (kick or similar)
Ask all - In your professional opinion – do you think Brandon Coates is responsible
for the death of David Short?
Thank you, I have no more questions for these witnesses.
(now, change hats and become the defense attorney)
I’m the defense attorney and I am representing Brandon Coates in this case. I would simply like to ask each of you a question about blood spatter analysis to see how qualified you really are as an expert witness in this subject.
(Each student in the group should be asked one of these questions. Each student must answer their question without help from other group members. These questions are for an individual grade (not a group grade). Each student will either get their question right and earn 30 points – or get their question wrong and earn no points.)
#1 - What measurements do you need to know to correctly calculate
the Impact Angle of a blood drop? (drop width and drop length)
#2 - What measurements do you need to know to correctly calculate
the Point of Origin of a blood drop? (Impact Angle and distance to Point of Convergence) #3 – Describe TWO things you could look for on a blood drop to help you identify the direction the drop was traveling when it hit the surface. (1. the pointed side 2. the tail or spike 3. any
satellites - would be on the side of the drop opposite the source)
Thank you, I have no more questions for these witnesses.
You can give students the correct answers and their group/individual grades before they leave, but make sure they know not tell other groups the questions they will be asked.
/ -5 / -5 / -5 / -5 / -5 / -5 / -5 / -5 / -5 / -5
Total Score =
________/ 125
30 pts. 0 pts. 30 pts. 0 pts. 30 pts. 0 pts.SAMPLE PAGES
IMPACT #1
About 2’ 6” to the left
of Evidence Blood Drop #1 Height of Im pact is about 5’ 7”, 67”, or 171cm Point of Ori gin is about 2’ 5”,
29”, or 73cm away from the
wall David Short was likely standi ng and hit in the f ace
at this location (he was
about 6’1” tall acc ording to police information) #1 #2 #3 #4 #5 #6 #7 #9 IMPACT #2
About 2’ 2” to the right
of Evidence Blood Drops #2 and #3 Height of Im pact is about 4’ 8”, 56”, or 143cm Point of Ori gin about 1’ 10”,
22”, or 55cm away from the
wall
David Short
was likely bent
over when
hit at this location
IMPACT #3
About 1’ 8” to the left of
Blood Drop #8 Height of Im pact is about 10” or 26cm Point of Ori gin about 1’ 7”,
19”, or 47cm away from the
wall
David Short
was likely ly
ing
on the ground and was
most
likely kicked at this location
1 Foot
FLOOR
FLOOR
Key To The Crime – Blood Spatter Evidence
(Not drawn to
perfect
scale)
#8
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Table 1 – Typical measurements and calculations taken from the blood spatter evidence. The values calculated below will vary slightly from group to group depending on where each group establishes their Points of
Convergence Evidence Blood Drop # Width (mm) Length (mm) Impact Angle Distance to Point of Convergence Point of Origin Average Point of Origin Height of the Impact #1 14 20 44.4o 74cm29" 72.5 cm28.5" #5 14 27 31.2o 119.5cm47" 72.4cm28.5" #9 13 31 24.8o 162.5cm64" 75.1cm29.5" #2 13 20 40.5o 65cm25.5" 55.5cm22" #3 15 25 36.9o 70cm27.5" 52.6cm20.5" #7 12 24 30o 99cm39" 57.2cm22.5" #4 11 32 20.1o 133cm52.5" 48.7cm19" #6 13 21 38.3o 60.5cm24" 47.8cm19" #8 12 18 41.8o 50cm20" 44.7cm17.5" 2' 5" 29" 73.3cm 5' 7" 67" 171cm 4' 8.5" 56.5" 143cm 10" 26cm
Impact #2
Impact #3
1' 9.5" 21.5" 55.1cm 1' 6.5" 18.5" 47.1cmImpact #1
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REFERENCE PAGE – GLASS AS EVIDENCE NAME____________________________ The Story Of Glass
*Glass can be important evidence at a crime scene – for example: glass with bullet holes can help tell the story of the shooting, and glass fragments found on a suspect can be matched to broken glass found at the crime scene.
*Glass is commonly made by melting sand (silicon dioxide – SiO2), a little lime (calcium
oxide –CaO), and a little soda (sodium carbonate – Na2CO3) together – which takes a
temperature of around 2100o F. When cooled, the resulting material forms the clear,
hard material we call glass.
*Different kinds of glass can be made by changing the recipe and adding different metal oxides – like boron oxide and lead oxide. Each kind of glass has slightly different properties.
*Kinds of glass, their uses, and their special properties can be found in Table 1 below.
*Colored glass is produced by adding various metals to the molten glass. For example: cobalt oxide produces blue glass, iron oxide produces green glass, nickel oxide produces violet glass, and selenium oxide produces red glass.
NAME USES SPECIAL PROPERTIES HOW IT IS CONSTRUCTED
Soda-Lime Glass
windows, bottles, drinking
glasses, etc. common glass sand + lime + soda
Borosilicate
Glass car headlights, pyrex dishes, lab beakers/test tubes
heat resistance glass - can be heated/cooled rapidly without
cracking
boron oxide is added to the glass
Lead Glass /
Lead Crystal decorative glassware like bowls, vases, crystal clear, sparkling glass for decoration lead oxide is added to the glass Tempered Glass /
Safety Glass
side and back windows in cars, some doors and windows in
homes and businesses
doesn't break like normal glass - breaks into small squares, which is less likely to cause
cuts/injuries
glass is stressed by rapidly heating and cooling during
production Laminated
Glass front windshield in cars
breaks like ordinary glass, but pieces stick to plastic, which
prevents cuts/injuries
a layer of plastic is sandwiched between two panes of glass Optical Glass /
Crown Glass / Flint Glass
lenses for glasses, telescopes, microscopes, etc.
very clear glass with few impurities - gives a very clear
view when used as a lens
very purified materials are