1. Blood Typing 1901 – Karl Landsteiner (Austria) discovered blood groups
Won the Nobel Prize in Physiology or Medicine in 1930
Before this, many patients died of blood transfusions due to blood clumping.
Clumped RBC’s can crack and cause toxic reactions.

2. Wet Samples vs. Dry Samples
Wet Samples can tell an investigator:
Is it blood?
Human or animal?
Type and subgroups
Blood alcohol content
Venous, fetal, or menstrual?
Presence of drugs
Possible ways the blood was deposited

3. Reliability in Court
Can NOT be used to positively ID a person, but CAN be used to rule someone out.