Forensic serology is the study and use of blood and other bodily fluids in investigating and solving criminal cases. This field of study typically focuses on blood evidence, though other fluids such as saliva and semen can also be used and provide a great amount of information. Blood evidence at a crime scene, especially a violent crime, can be used to establish certain information about a victim or possible suspect, including gender, age range, and likely ethnicity. Forensic serology is often closely tied to the study of deoxyribonucleic acid (DNA) and may be involved with DNA typing and analysis.
The field of forensic serology can be pursued by serologists as well as biologists and medical examiners. Some criminal investigation facilities may have a dedicated forensic serologist, though this is fairly rare and investigation into blood evidence is typically handled by other forensic lab technicians. Blood evidence is one of the most prevalent and important types of evidence, especially for violent crimes, and can be used in reference to victims and assailants alike. Through forensic serology, the cause of death for a victim can sometimes be determined, and any blood evidence or other bodily fluids left at a crime scene can be traced to potential suspects.
Forensic serology will often study the blood of a body found at a possible crime scene to help establish the cause of death. A blood sample can be examined for toxins that might indicate the presence of drugs or poisons within a person’s system, which may have caused his or her death. Similarly, through DNA analysis, a person can potentially be identified without recognizable features, dental records, or fingerprints by comparison to other samples of DNA. Though forensic serology is not always used to analyze DNA evidence, the two fields have become increasingly interconnected as technology has advanced.
This type of DNA evidence, often analyzed through forensic serology, can be used to help find perpetrators of crimes as well. If blood or other fluids not belonging to a victim are found at a crime scene, it can be analyzed to gain information about possible suspects. DNA and blood can indicate the gender of a person, give hints to age through the presence of vaccines or diseases, and even suggest ethnicity based on common traits found in blood. Once a suspect is found, DNA matching can often be used to either prosecute or release a person, as the blood and other bodily fluids can create a direct link between a violent crime scene and an assailant.