Blood evidence is a powerful crime-fighting tool in forensic investigations.
By analyzing the blood found at the scene of a crime, forensic scientists can help determine the identities of victims and perpetrators, determine the manner of death in homicides, and exonerate innocent suspects. One technique that has been widely used in forensic investigations is blood typing, or serology, which involves identifying the A, B, AB, or O blood types of individuals.
How can blood typing be used in forensics quizlet?
Blood typing can be used in forensics to:
- Identify the blood type of a victim or perpetrator
- Correlate blood evidence with other physical evidence
- Link crime scenes and suspects to each other
- Provide additional evidence to the prosecution or defense in court
What are 3 situations where blood typing could be used?
Blood typing can be particularly useful in a variety of situations:
1. Sexual Assaults
In cases of sexual assault, forensic scientists can use blood typing to determine if a victim’s blood and a suspect’s blood are present at the scene. If the victim’s blood and the suspect’s blood are of different types, it suggests that the suspect had been injured and bled during the assault. The suspect’s blood type can then be tested to determine if it matches the blood type present at the scene, providing crucial evidence for prosecution.
2. Paternity Testing
Blood typing can also be used in paternity testing to determine whether a man is the biological father of a child. If the child has a different blood type from the claimed father, it is impossible for him to be the biological father. In this case, more advanced DNA testing may be necessary to determine paternity.
3. Homicide Investigations
In homicide investigations, blood type analysis can help identify suspects and eliminate innocent individuals. Blood typing can also provide insight into the manner of death – for example, if there are large amounts of blood present at the scene, it may suggest that the victim was killed via blunt force trauma or multiple stab wounds.
When was blood typing first used in forensics?
Blood typing was first used in forensic investigations in 1901 by Austrian physician Karl Landsteiner, who discovered the ABO blood group system. His discovery of blood groups revolutionized transfusion medicine and ultimately led to improvements in forensic science.
How are blood samples used to solve a crime?
When blood is collected from a crime scene, it is typically collected in vacuum-sealed tubes that are properly labeled and sealed to maintain the integrity of the sample. The blood is analyzed in a forensic laboratory, where it undergoes a series of tests to determine its blood type.
Once blood typing is completed, the forensic scientist can compare the blood type of the victim or perpetrator to other physical evidence found at the scene, including fingerprints, hair, or DNA samples. This helps to identify potential suspects and link them to the crime scene.
It is important to note that blood typing is not foolproof and cannot provide definitive identification evidence on its own. However, when combined with other forensic science techniques, it can be a powerful tool in solving violent crimes.
References
- “Blood Typing”. Encyclopædia Britannica. Encyclopædia Britannica, Inc., 2017, www.britannica.com/science/blood-group/Blood-typing. Accessed 1 Aug. 2021.
- “Forensic Blood Typing”. Serological Research Institute, 2021, forensicscience.sri.com/forensic-blood-typing. Accessed 1 Aug. 2021.
- “Forensic Serology: A Brief Introduction”. The Investigator’s Notebook, 2021, www.theinvestigatorsnotebook.com/forensic-serology-a-brief-introduction/. Accessed 1 Aug. 2021.