What type are the 8 blood types?
A+/- B+/- AB+/- O+/-
What are 'spines' on a drop of blood? What kind of surface would create spines?
Spines radiate out from a blood drop when it falls. Harder surfaces create more spines
What information does the 'tail' of a blood drop provide?
It points in the direction the blood was moving so we can determine the direction the blood came from.
What is the purpose of a Presumptive Test?
To determine if a stain is blood or not blood.
Which famous serial killer was recently played by Zach Effron?
Ted Bundy
What type of blood cell carries the protein that determines blood type?
Red blood cells
What are satellites in a spatter pattern? What would cause them to form?
Satellites are small drops of blood that spring off the main drop of blood. They form from blood dropping from a great distance particularly onto more blood.
What formula do we use to determine the angle from which a blood drop came? How can you tell which is the width and height of a blood drop?
sin-1(height/width). The height is always the larger number.
What is the purpose of chemical treatments such as Luminol, Fluorescein and Leuco Crystal Black?
These chemicals can show latent blood stains (those that cannot be seen with the naked eye).
Although never convicted for the murder of nearly 30 children in Atlanta, this man was convicted of two murders using fiber evidence- the same fiber evidence found on many of the unsolved murders.
Wayne Williams- Atlanta Child Murders
What are the 3 proteins that may be found in in a blood sample?
A. B. Rhesus (+/-)
A bloody handprint on a wall. What type of bloodstain pattern is this?
Transfer pattern.
Describe the different velocities of blood and what would you expect to find with each one?
Low velocity- larger drops or pools of blood
Medium velocity- smaller drops that are flung with force-not perfect circles
High velocity- very small drops that create a misting pattern.
What is the most common blood type in the world?
O+
This part time politician and socialite also had a side gig as a party clown. He was later found to have killed 33 young men. He buried them in his basement and back yard without his wife ever finding out.
John Wayne Gacy. The Killer Clown.
What blood type does this person have?
AB-
What type of blood pattern is this?
Wipe patter
As the angle of impact for a blood drop becomes smaller, the shape of the blood drop....
becomes more elongated
A victim was attacked and defended himself with a pocket knife. He managed to cut his attacker on the arm. The blood on the knife was analyzed and found to be AB-. A suspect was brought in with a cut on his arm. This suspect had AB- blood. What type of evidence is this blood (class or individual)?
Class. Blood type is always class evidence.
However-the blood can be DNA analyzed and if that matched then it would be individual.
There has been talk of Leonardo DiCaprio playing this late 1800's killer from Chicago. He was famous for constructing a "Murder Hotel" with hidden doors and hallways and gas vents that will kill guests in their sleep and shoots that would send bodies down to the basement. He would sell their skeletons to the local universities.
HH Holmes
You want to know if B protein is present in a blood sample. Describe how you would find out.
Add anti-B serum to the sample. If the blood clumps, the protein is present.
What type of blood pattern is this? What velocity is this type of pattern? What are two things this type of pattern can tell you?
Cast off. Medium. The approximate number of blows. The approximate location in the room during attack. Approximate size of the weapon
You have measured the angle of five different drops in the corn walls of a room. Describe how to use this information to determine where the victim was standing.
Extend lines out from each drop (using lasers or strings) at the calculated angle. The lines will cross at the approximate location of the victim when attacked.
Look at this image. Where do you think this might have been found? What type of surface is it on? Create a reasonable description for what might have happened.
This would be on a wall that is relatively smooth. There are spines and satellite drops which mean a large force of impact. Which means medium to high velocity. This could be the result of blunt force trauma.
Recently a long unsolved string of murders was solved using DNA test sites (such as 23 and me). Several people who participated were found to share DNA with the infamous serial killer and a family tree was constructed. This led to the arrest of an 75 year old former police officer- a husband and father- who was found guilty of 13 murders and over 50 rapes.
The Golden State Killer