Travis Alexander case
Review from last week
Injuries
Blunt force trauma
Sharp force trauma
Asphyxiation
Petechial Hemorrhaging
Hyoid Bone fractures
Gunshot
Contact, close,
medium and distant
Stippling
Angle of entry
Toxicology
Tissues, organs, and body fluids are retained
for pathological and toxicological examination.
►Blood – Contain most foreign chemicals
►Bile – Morphine, MDMA, buprenorphine, tramadol
►Brain – Morphine, cocaine and mercury
►Urine – Morphine, Meth., heroin, cocaine, THC
►Stomach contents – Orally admin. drugs
►Hair – All substances
►Vitreous humor – Alcohol, glucose, urea, creatine
►Blood is routinely tested to determine the presence and
levels of alcohol and drugs.
►Some drugs redistribute after death – post mortem
drug redistribution
Manner of Death
Manner of death relates to the circumstances that
led to the fatal result.
Five categories:
• Homicide
• Suicide
• Accidental
• Natural
• Undetermined
Estimating time of death
(Post-mortem index or PMI)
Stages of Physical Change
• Algor Mortis
• Livor Mortis
• Rigor Mortis
Algor mortis
0 hr
30 hr
TOD
Algor mortis body temperature continually cools until it reaches the ambient /
room temperature
Oral average body temp: 98.6°F (37°C).
May fluctuate a degree throughout day
Sensitive to hormone levels - women
Rectal or ear temperature higher than oral
• Armpit temperature lower than oral
• Body temperature – ear, rectal, or liver temperatures.
Taken at scene as soon as possible
Livor mortis
0 hr
16 hr
TOD
Livor mortis settling of blood in areas of body
closest to ground
• Blood settles in direction of gravity
• Begins 20 minutes after death and continues
up to 16 hrs.
• Lividity (coloring)
• Pinkish-red
• Deep purple with heart failure or asphyxia
• Different lividity pattern  body possibly
moved
30 hr
0 hr
16 hr
30 hr
TOD
How do you know if someone is in the 16 hr. window?
Blanching of the skin
Applying pressure to area of livor mortis
might result in blanching for a time
• Blanches – within the 16 hr. window
• No change- Past the 16 hr. window
Light pressure on the skin
Blanching results
0 hr
16 hr
30 hr
TOD
Livor Mortis - Impressions
Clothes, fabric and objects pressing on the skin result in blanching patters.
Rigor mortis
0 hr
5 hr
TOD
Rigor mortis stiffening of the muscle mass
• begins 5 hours PM, head, neck
then extremities – disappears after
~36 hours.
• Occurs since body’s energy source
(ATP) is depleted
• Muscle needs ATP
to relax
30 hr
36 hr
0 hr
TOD
Decomposition
Decomposition decay or putrification, primarily
from intestinal microorganisms
• After death, no functional immune
system
• Abdomen develops green
discoloration after 24-36 hours
• Bacteria produces gas, causing
belly and face bloating
2-3 days after death
24 hr
36 hr
Discoloration
0 hr
TOD
24 hr
36 hr
Discoloration
Decomposition
Corneal Clouding
Present in the early stages of decomposition
Corneal clouding
0 hr
TOD
Decomposition
Decomposition in lower abdomen
24 hr
36 hr
Discoloration
Marbling of the skin
0 hr
4 days
1 day
9 days
15 day
TOD
Blowfly Life cycle
1 day
Eggs hatch
Larvae emerge
Larvae grow
5 days
Blowfly lays eggs
6 days
Prepupation
Larvae forms a hard
cocoonlike shell
Fundamentals of crime scene reconstruction
Objectivity: Lack of bias, judgment,
or prejudice
Personal beliefs can result unlikely
theories and pursuits
Juries rely more on forensic evidence
to support a story.
Expert testimony will uncover
investigative bias.
Objectivity
Deductive Reasoning: Use facts in the
case to guide you to a logically certain
conclusion
Inductive Reasoning: Attempt to reach a
conclusion based on little evidence
Testing a theory
Falsifiability: Attempt to disprove your theory.
Never try to prove a theory
Investigators try to avoid:
Limiting the number of suspects too
early
Discarding important forensic evidence
Ignoring important story lines
Selecting evidence that agrees with your
storyline
Fingerprint principles
Fingerprint theory works on three
principles:
1) A fingerprint is an individual
characteristic
2) A fingerprint remains unchanged
during an individual’s lifetime
3) Fingerprints have feature that permit
them to be systematically classified
Letter from the Zodiac Killer
Level 1 Features:
Loop
Whorl
Arch
Level 2 features:
Ridge characteristics
Level 3 features:
Everything else that isn’t
a ridge feature.
The Scientific Methodology called ACE-V
Analysis– the qualitative and quantitative assessment of
Level 1, 2, and 3 details to determine their proportion,
interrelationship and value to individualize.
Comparison– to examine the attributes observed during analysis
in order to determine agreement or discrepancies between two
friction ridge impressions.
Evaluation– the cyclical procedure of comparison between two friction ridge impressions to effect a
decision, i.e., made by the same friction skin, not made by the same friction skin, or insufficient detail
to form a conclusive decision.
Verification– an independent analysis, comparison and evaluation by a second qualified examiner of
the friction ridge impressions.
How IAFIS works
►Integrated Automated
Fingerprint Identification
System (IAFIS)
►Launched July 1999
• Fingerprint examiner and/or
computer program select
most distinct features in
fingerprint
• Position and orientation of
minutiae also recorded
• In other words, digitally
recorded geometric pattern
Bloodstain pattern analysis
Chapter 10
Surface Texture
Hard & nonporous surfaces
• (e.g., glass, tile, Linoleum) = less spatter
Textured surfaces
(e.g., concrete & wood) result in
irregularly shaped stains with spiny
edges and satellite spatter.
Satellite
Spines – Blood stains extending from
and connected to a blood droplet
Satellite spatter – Small blood stain
droplet that originated from but not
attached to a larger blood stain
Spines
Direction
• Direction blood was moving
• Direction bleeding or bloody
person/object was moving
• Determined by the
bloodstain’s shape
Convergence
-Point on a 2-dimensional plane from
which the drops originated.
Only requires the direction of blood
spatter to determine the convergence
Angle
Direction blood was moving
Direction bleeding or bloody
person/object was moving
𝜽
• Determined by the
bloodstain’s shape
Angle the blood struck the
surface
Width
Sin(θ) =
Length
θ = Sin
−1
Width
Length
Width – 4 mm
Length – 6 mm
𝛉 = 𝐒𝐢𝐧−𝟏
𝛉 = 𝟒𝟐 °
𝟒 𝐦𝐦
𝟔 𝐦𝐦
𝛉 = 𝟒𝟐 °
Area of origin
Location of blood source in 3D space
1 Determine the point of convergence
2 Use the angle to determine the height
of the blood source.
𝛉
𝛉
𝛉
Types of Blood stains
Passive Blood Stains
Transfer Blood Stains
Projected
Low velocity (5ft/sec)
Medium velocity (5-25ft/sec)
High velocity (>25ft/sec)
Cast-off
Arterial
Transfer pattern
Can reveal Class or even Individual
characteristics of the item that
transferred the blood.
Class characteristics
Brand of the object (Nike shoes)
Individual characteristics
Unique wear pattern
A Specific pair of shoes (Ryan’s Nike
shoes)
Low velocity
• https://www.youtube.com/watch?v=-tXdhXyVDWg
• Large, separate, or compounded drops
• Up to 5 ft/sec
• Stains 4 mm or greater
• Produced by
• Gravity (passive)
• Cut on your finger that drips onto the floor
Low Velocity Spatter – passive (gravity)
Low Velocity Spatter
Droplets contain a
relatively large volume of
blood.
Often produce:
Satellite spatter
Spines
Medium velocity
5-25 ft /sec
Source:
Bat
Wrench
Pipe
Hammer
Club
Car Accident
Fall
Spatter Location
No spatter after first blow
Medium velocity
Small drops
• 5-25 ft/sec
• Stains 1- 4 mm
Usually seen with
• Blunt force trauma
High velocity
• https://www.youtube.com/watch?v=agmwXwnWDBw&list=PLk3y66BvSLX8MfStq7lOnfSeqp0Vb1XA&index=50
Very fine droplets or mist
• 100+ ft/sec
• Stains less than 1 mm
• Often from gunshot wounds
Blood spatter from a gunshot wound
1 Small blood spray from the exit wound
2 Drawback effect: Back spatter
3
from entrance wound
3 Investigator searches for:
Spatter on shooters clothes or
weapon
3
3
2
1
Gunshot Spatter
• Gunshot spatter is characterized by fine forward spatter from an exit wound
and back spatter from an entrance wound.
• Back spatter may strike the gunman and enter the gun muzzle. This is called the
drawback effect
Outline
Crime scene reconstruction
Brandon Dassey Confession
Oscar Pistorius
Jodi Arias Case
https://youtu.be/A2XvzoNqUh8
Warning!
The following slides will include
crime scene photos and autopsy
photos
Travis Alexander blood spatter evidence
Consider what type of blood evidence
is in each photo.
Timeline
Sequence of events
Bedroom
Jodi Arias Case – June 4 2008
Mesa, Arizona
Hall
Closet
Body was
found here
Closet
Shower
Bathroom
Travis (deceased) in the shower
Blood stain in the shower
Bedroom
Jodi Arias Case Crime Scene
Hall
Closet
Closet
Shower
Bathroom
What do the photos tell you about the
attack?
Prosecution:
Travis is seated for a photo
Vulnerable in this position
Attacked first with a knife
Autopsy photo of Travis
Chest wounds were the
first injuries that Travis
suffered
Orientation of the wounds
indicate the attacker was
perpendicular to the body
Bloodstaining on the sink
Bedroom
Jodi Arias Case Crime Scene
Hall
Closet
Closet
Shower
Bathroom
Bloodstaining on the sink
Bedroom
Jodi Arias Case Crime Scene
Hall
Closet
Closet
Shower
Bathroom
Autopsy photo of Travis
Wounds suffered in front of the mirror
Head and back wounds:
Pool at the sink
Spatter on the mirror
All suffered while standing at
the sink
Bloodstaining on the wall
Bedroom
Jodi Arias Case Crime Scene
Hall
Closet
Closet
Shower
Bathroom
Blood smearing down the hallway supports Travis
attempted to escape
Bedroom
Jodi Arias Case Crime Scene
Hall
Closet
Closet
Shower
Footprint and handprint evidence helps to place Jodi
Arias at the crime scene
Bloodstaining in the hallway
Bathroom
Bedroom
Jodi Arias Case Crime Scene
Hall
Closet
Closet
Shower
Bathroom
Blood was cleaned up in the hallway and bathroom
Bloodstaining on the carpeting
Bedroom
Jodi Arias Case Crime Scene
Hall
Closet
Closet
Shower
Bathroom
Blood staining on the carpet suggests a lot of activity in
this area.
Small blood stain and shell casing
Bedroom
Jodi Arias Case Crime Scene
Hall
Closet
Closet
Shower
Bathroom
Medical Examiner stated, “There was little to no bleeding
from the gunshot wound. This is because Travis had
already sustained two significant arterial injuries.”
Jodi’s Interview with police
Jodi changed her story 3 times about the crime scene including where she
was during the murder
Jodi deleted murder photos from the camera and wiped up blood with a
towel.
Prior to the murder
2 June
Jodi leaves Yreka, CA where
she was living.
Multiple calls to Travis
Prior to the murder
2 June
Jodi leaves Yreka, CA where
she was living.
Multiple calls to Travis
3 June
Jodi’s ex boyfriend gives her
a couple of gas cans for her
roadtrip.
Prior to the murder
2 June
Jodi leaves Yreka, CA where
she was living.
Multiple calls to Travis
3 June
Jodi’s ex boyfriend gives her
a couple of gas cans for her
road trip.
4 June – 4AM
Jodi’s arrives in Mesa, AZ
5:22 Travis is stabbed and
shot
After the murder
5 June
Jodi stays with Ryan Burns –
a friend.
Burns noticed cut marks on
her hands and fingers.
After the murder
5 June
Jodi stays with Ryan Burns –
a friend.
Burns noticed cut marks on
her hands and fingers.
6 June
Jodi drives through Salt
Lake City, UT.
After the murder
5 June
Jodi stays with Ryan Burns –
a friend.
Burns noticed cut marks on
her hands and fingers.
6 June
Jodi drives through Salt
Lake City, UT.
7 June
Returns home
Jodi Arias
The gun that was used was a 0.25 caliber handgun. It was never recovered
Prosecution claims the gun was stolen from her grandfather two weeks earlier
and she is the one who had stolen it.
Case review
What did blood spatter tell
you about this case?
• 2 Arterial wounds
• Expirated blood on the
sink
• No staining from the
gunshot wound
• Transfer pattern with:
•
Jodi’s palm print
•
Jodi’s shoe print
What was the sequence of
events?
Gunshot first or last?
Jodi Arias and Travis Alexander