Blood Spatter October 11 2018 Early on the

Blood Spatter October 11, 2018

Early on the morning of July 4, 1954 police received a call from Dr. Sam Sheppard. He reported that his wife had been killed the night before. Sam & Marilyn Sheppard Sam Sheppard Case

Sam’s Story • He went to sleep on the couch • Heard his wife shout “Sam”and awoke • Found a person standing by his wife’s bed. They struggled, Sam was hit on the back of the neck, and lost consciousness. • When he awoke, he found his wife covered in blood. He took her pulse and found that she was dead. Marilyn, partially undressed and covered in blood. Sam Sheppard Case

Sam’s Story • When he regained consciousness, the intruder was gone. • He checked on sleeping son next door – he was fine. • Went downstairs and saw intruder leaving. • Chased and battled the “tall bushyhaired” intruder on the beach, was choked, and again lost consciousness • Awoke in the morning, wet & missing his shirt and watch. Sheppard (? ) with a neck brace Sam Sheppard Case

Police investigation • Marilyn was found in bed, with her clothes partially removed and covered in blood • More than 20 blows to her head • Appearance of staged robbery Crime scene sketch of Sheppard home Sam Sheppard Case

Police investigation • Marilyn was found in bed, with her clothes partially removed and covered in blood • More than 20 blows to her head • Appearance of staged robbery Quote from Marilyn’s friend’s husband, who was allowed to view the scene: "Oh my God. It looks like someone stood in the middle of the room with a great big can of red paint and a brush and flicked it all around. This wasn't a couple of blows. Oh no. Whoever did it, they had to be out of their mind. “ Sam Sheppard Case

1954 Trial • Police quickly concluded the Sheppard killed his wife and (perhaps) did a somewhat sloppy job examining the evidence • The case garnered a lot of publicity, and the press was very hostile to Sheppard • The trial had “carnival-like atmosphere” and the defense offered little evidence other than Sam’s story and injury. • Convicted and sentenced to life in prison. Sam Sheppard Case

Supreme Court Verdict • In 1966 the Supreme Court overturned Sheppard’s conviction, arguing that he did not receive a fair trial due to the publicity surrounding the trial Sam Sheppard Case

1966 Retrial • Respected criminalist Dr. Paul Kirk re-examined the blood spatter evidence and testified for the defense • Blood spatter consistent with left-handed killer (Sam Sheppard is right-handed) • Blood on Sheppard’s watch and clothing was transferred blood not back spatter • Sheppard was pronounced not guilty. The End … or is it? Sam Sheppard Case

2000 Civil Trial • In 2000, Sam Sheppard’s son sued the county for wrongful imprisonment. • The jury sided with the county, and 6 of 8 jurors said they believed Sheppard to be the murderer. So … is he guilty? No one knows. The TV show and movie “The Fugitive” were loosely inspired by the case Sam Sheppard Case

Blood spatter – the patterns left on a crime scene by blood – can be used to help reconstruct the events of a crime. By observing spatter, you can determine • The direction of travel • The angle of impact • The position origin • The droplet’s speed What can you learn from blood spatter?

Passive blood • Blood drops that form by the force of gravity, alone. • Example: Blood dripping or oozing from a wound or a weapon A murder throws a bloody knife into the bushes, leaving blood spatter on the Projected blood grass. Is this passive blood • Blood drops that form when something other than or projected blood. Why? gravity applies a force to the blood. • Example: Arterial pressure, blunt force trauma, gunshot, etc. Classifying Spatter

Talk with a partner, and take a guess … How will each of these factors affect passive blood spatterns? 1. Distance of dropping 2. Angle of impact 3. Surface of impact Passive Blood Spatter Patterns

Distance of Dropping • Passive blood falls due to gravity • Accelerates until reaching terminal velocity • Higher the fall faster the velocity of impact (up to a point) • Terminal velocity is ~25 ft per second, occurs with fall of ~5 ft • Faster velocity / Higher fall = larger diameter of drop. Which drop fell from the greatest height? The drop on the upper left. Passive Blood Spatter Patterns

E B D A C F Match each stain from the height with the heights at which they were dropped. Assume the same amount of blood fell with each drop Heights: 1. 5 ft, 2 ft, 3 ft, 5 ft, 7 ft, 10 ft Passive Blood Spatter Patterns

E B D A C F Match each stain from the height with the heights at which they were dropped. Assume the same amount of blood fell with each drop Heights: 1. 5 ft (E), 2 ft (C), 3 ft (B), 5 ft (? ), 7 ft (? ), 10 ft (? ) Why don’t A, D, and F vary much in size? Passive Blood Spatter Patterns

E B D A C F Match each stain from the height with the heights at which they were dropped. Assume the same amount of blood fell with each drop Heights: 1. 5 ft (E), 2 ft (C), 3 ft (B), 5 ft (? ), 7 ft (? ), 10 ft (? ) Why don’t A, D, and F vary much in size? Blood reaches terminal velocity at about ~5 ft. Passive Blood Spatter Patterns

Angle of Impact • Drops that hit at a 90 O angle (i. e. straight down) form an even circle. • Drops that hit at other angles form an elongated oval • The longer the oval, the shallower the angle of impact Passive Blood Spatter Patterns

• 3 cm 5 cm Angle of impact = arcsine (3/5) = 37 degrees Passive Blood Spatter Patterns

You do: Find the angles. Which drop had a greater angle of impact? The on the left What does it mean to have a greater angle of impact? The greater the angle, the • 2 cm 30 degrees 4 cm 3 cm 49 degrees 4 cm more perpendicular (straight down) the drop lands. Passive Blood Spatter Patterns

Surface of Impact Drops falling onto smooth, non-porous surfaces have smooth edges (they don’t splash). Drops falling onto rough surfaces produce spiny / irregular stains and possibly satellite spatter. Satellite spatter are the small drops that surround a central drop. They form when the blood splashes after hitting the surface. Spatter on tile Spatter on wood Passive Blood Spatter Patterns

Think, Pair, & Share. What can you tell me about this spatter?

The source of blood spatter can be localized by following the direction of travel of several stains. Direction of travel The narrow end of an elongated blood stain usually points in the direction of travel Points of origin and convergence

The source of blood spatter can be localized by following the direction of travel of several stains. Point of convergence By using string to back-track the trajectory of blood stains in 2 -D space, you can find the point of convergence Points of origin and convergence

The source of blood spatter can be localized by following the direction of travel of several stains. Point of origin By using string to back-track the trajectory of blood stains in 3 -D space, you can find the point of origin Points of origin and convergence

What is the difference between the point of origin and point of convergence? Point of origin is in 3 D space, point of convergence is in 2 D space. How can you determine the height from which the blood fell? Find the angle of impact using sin-1 (width/height) Points of origin and convergence

We already classified spatter as passive or projected. What is the difference between these? Passive – no force applied to blood other than gravity. Example: blood dripping from a knife Projected – force is applied to the blood Example: blood spatter from gunshot wound Spatter can also be classified by velocity or by mechanism of projection. Classifying Spatter

Spatter can be classified by the velocity of the projecting force (not velocity of the blood itself). Low Velocity Impact Spatter (LVIS) – When source of blood is subjected to a force with a velocity of up to 5 feet per second. Primary stains are usually greater than 3 mm in diameter. Example: This spatter often occurs after an injury, Classifying Spatter by Velocity

Medium Velocity Impact Spatter (MVIS) – When source of blood is subjected to a force with a velocity of 5 to 25 feet per second. Most stains will range from 1 -3 mm in size. Example: beating with fists or blunt objects High Velocity Impact Spatter (HVIS) - When source of blood is subjected to a force with a velocity of 30 feet per second or more. Most stains will be smaller than 1 mm in size. Example: gunshot wound or explosion Classifying Spatter by Velocity

How does the velocity of the impact object affect blood spatter? The higher the velocity of impact, the smaller the size of the spatter. Are these the same patterns you would expect if the blood was traveling at these speeds? Why or why not? No, the patterns are opposite. When the blood itself travels at higher velocity, the spatter is larger. Classifying Spatter by Velocity

• Back spatter / blow back – blood that comes out an entrance wound; often lands on the weapon and/or perpetrator • Forward spatter – blood associated with an exit wound Classifying Spatter by Mechanism

• Expirated blood – blood that is blown out of the nose, mouth, or wound as a result of air flow Often small, diluted with saliva, and may have bubbles • Cast-off pattern – blood stains pattern created when blood is released from a moving, bloody object (e. g. a bloody knife swung through the air) Often large drops in a linear or arcing pattern Classifying Spatter by Mechanism

• arterial bloodstain pattern – bloodstains resulting from blood projected out of a damaged artery Often form a large spurting pattern • transfer pattern – a bloodstain created when a bloody object touches another surface Classifying Spatter by Mechanism

• Wipe pattern – blood stain created when an object moves through an existing stain Example: The murder pulls the body across the blood-stained floor • Swipe pattern– the transfer of blood from a moving source onto an unstained surface Example: the murder touches the unstained wall with bloody hands as he walks away Feathered edge shows direction of travel Classifying Spatter by Mechanism

• Void pattern – Areas that are absent of blood stains in an area that is otherwise full of blood stains Example: Can occur if a bloody item was removed from the scene Classifying Spatter by Mechanism

Read answer the questions: What kind of pattern was found on Dillon’s ears? What kind of pattern was found on the tree stump and Scher’s boots (catergorize it in two ways!) The article mentions that the blood on the stump shows that he was seated, not running … how might those two patterns look different?

Crime scene reconstruction based upon blood spatterns requires extensive training, and even then, is prone to error. • Most respected certification program is from the International Association of Bloodstain Pattern Analysis. It requires 40 hours of workshop instruction followed by 3 years of practice in the field. • No uniform standards for interpretation! • NIJ did a study and found 37% error rate in classifying spatterns. Blood Spatter Reconstruction: Proceed with Caution!