If you’re interested in science and crime scene investigation – and you’re not squeamish about human body fluids – you might make an excellent forensic serologist. You’re most likely to find forensic serologists in a crime lab analyzing evidence samples.
This forensic specialist needs a minimum of a bachelor’s degree combined with on-the-job training in a laboratory setting.
What Is Forensic Serology?
To put it simply, serology is the term for applications of the scientific field of study concerned with bodily fluids to matters involving the legal and court system, particularly matters of criminal investigations.
What Is Serology?
Officially, serology refers to the study of blood serum, a liquid found in blood plasma after the blood coagulates or, in other words, clots. On its own, serology is considered a medical science. Serologists who work as medical personnel are primarily interested in the immunological properties of blood serum – that is, properties that pertain to the body’s immune system and its functions in fighting off infections and other harmful invaders or exposures.
Antibody tests used to establish a history of prior infections, like COVID-19, are an example of a type of serology test used in medicine rather than forensics, the Food & Drug Administration (FDA) reported. Serology tests are blood tests conducted to determine if antibodies produced by the immune system are present. Different infections produce different antibodies, so a blood test can distinguish the proteins produced to fight COVID-19 infection from those produced by other infections, such as seasonal influenza.
Forensic Serology Definition
For forensic serologists, the inclusion of the term “forensic” in the job title is critical. This term is what establishes that the serologist isn’t a medical scientist or biological research scientist but rather an expert in forensic, or criminal investigation, applications of this scientific study.
Forensic serology is one of the specialties that belong to the field of forensic science. All specialties of forensic science apply scientific principles and methods to the examination of evidence in legal matters or criminal investigations. The purpose of forensic science methods is to apply scientific techniques to the analysis of evidence pertaining to a criminal investigation to reach “objective” findings that demonstrate a person’s guilt or innocence, according to the Department of Justice.
Types of Evidence in Forensic Science
Forensic science technicians, as a whole, examine evidence of all kinds. Outside of a forensic serology unit, forensic scientists examine evidence like the following:
- Hair and other fibers found at the crime scene, on a weapon or on the victim or a suspect
- Trace evidence, or microscopic evidence that may include soil, broken glass, paint, polymers and other chemicals
- Poisons, toxins and other chemicals
- Explosives and fire or arson accelerants
- Firearms and tool marks
- Ballistics, or the mechanics of projectiles such as bullets
- Digital evidence, or evidence found on a computer, smartphone, or another mobile device
The forensic science specialty of serology can encompass the study of DNA analysis and blood spatter interpretation. Forensic scientists also include careers like forensic biologist and forensic chemist.
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What Do Forensic Serologists Do?
Forensic serologists spend their workdays in much the same way as technicians in other specialties of forensic science. They may visit a crime scene where they will collect blood samples and any other types of biological evidence found at the scene, according to National University. Once they return to the crime lab, where they spend most of their time, forensic serologists examine samples and run tests. They report the findings of their tests to law enforcement agencies.
Forensic Serology’s Findings in Criminal Investigations
Sometimes a forensic serologist’s findings may establish that a suspect or person of interest in criminal investigations is innocent. Other times, the findings produced through forensic serology testing are what make it possible for law enforcement agencies to get a warrant to arrest a suspect or execute a search or to charge the suspect with the crime.
In court, the prosecutor may present the findings of tests performed on biological samples as evidence of the defendant’s guilt. Securing the conviction of the guilty party may come down to the biological and DNA evidence identified by a forensic serologist.
The stakes are high. If a forensic serologist fails to report their findings by the deadline required, it could jeopardize criminal investigations. Similarly, if the forensic serologist does not follow the proper protocol for collecting and handling the evidence, the guilty party may never face justice for their crimes.
Types of Body Fluids in Forensic Serology
Despite the job title, forensic serologists aren’t concerned only with blood serum or even blood as a whole. Rather, forensic serologists are involved in testing bodily fluids of all kinds, including:
- Breast milk
- Any other biological materials, or other bodily fluids
Forensic serologists encounter environmental hazards in their work, since the bodily fluids they examine could be contaminated or carry infections. As a result, it’s essential that forensic serologists follow the proper safety protocols at all times when handling or analyzing evidence in the field or in the crime lab.
Types of Tests in Forensic Serology
When forensic serologists examine samples, they conduct a variety of evidence-based tests as part of the course of a normal forensic investigation.
In testing bodily fluids like blood, saliva and semen, forensic serologists perform analyses that fall into two general categories.
Presumptive tests, also called screening tests, are chemical tests that can establish the possibility that bodily fluids are present in the tested material. The chemical reaction produced through testing typically produces a light or color that signals the potential presence of bodily fluids, according to the Oklahoma State Bureau of Investigation.
Because this type of test screens for the possibility that a substance contains bodily fluids, it has to be sensitive enough to detect even small amounts of the fluid. A presumptive test doesn’t tell the forensic serologist specifically what fluid is found. Instead, it establishes that further analysis is needed.
Presumptive test examples include the following:
- The luminol test, a test in which the chemical luminol (combined with an oxidizing agent) is used to identify trace amounts of blood at crime scenes that couldn’t be seen with the naked eye. When the luminol comes into contact with the iron found in blood, it reacts by emitting a glowing blue light.
- The phenolphthalein test, also called the Kastle-Meyer color test, in which a solution made of phenolphthalein and hydrogen peroxide is applied to a suspected blood stain. The test produces a bright pink shade if it reacts to the hemoglobin found in blood.
- The acid phosphatase test, a test used to indicate the presence of seminal fluid in an evidence sample. When a stain suspected to contain seminal fluid is sampled with a swab and exposed to acid phosphatase solution, the reaction of the solution to seminal fluid will result in a purple color in just two minutes.
Confirmatory tests are the more specific methods of testing bodily fluids to verify that the specimen does, in fact, contain body fluids and establish what body fluids are found there. If presumptive screening tests produce positive results, a forensic serologist or their fellow forensic specialists will run confirmatory tests like the following:
- The “Christmas tree stain” test for sperm identification, a test that allows for visual identification of sperm cells by applying stains – Picroindigocarmine and Kernechtrot, also known as Nuclear Fast Red – that dye the heads of sperm cells red and the tails green.
- RSID tests are a series of Rapid Stain Identification tests, each of which is used to confirm the presence of a specific body fluid. RSID tests exist for blood, saliva, semen and urine.
Forensic Serology and DNA Analysis
Although serology and DNA analysis are not the same, they are closely related topics that both serve the purpose of aiding criminal investigation work. A simple explanation, according to National University, is that forensic serology is concerned with collecting and analyzing samples of biological evidence to determine if blood or other bodily fluids are present, while DNA analysis refers to determining whose fluids they are.
To match the body fluids from a crime scene to an individual suspect or victim, forensic scientists must look at genetic markers or variations. Technical methods for studying the variations in genetic markers in DNA sequences are known as methods of DNA typing, the National Research Council (US) Committee on DNA Technology in Forensic Science reported. More specific methods used in DNA analysis include DNA fingerprinting and DNA profiling. DNA profiling refers to the forensic technique of identifying a pattern of characteristics. A DNA fingerprint is an individual’s unique, unalterable pattern of genetic variations that can be established using the laboratory techniques of molecular genetics. These terms are sometimes used interchangeably.
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DNA analysis is so critical for modern forensic investigation practices that not being able to obtain a DNA profile could potentially jeopardize criminal investigations. However, DNA tests take time to complete. Fortunately, some additional types of testing can be done on biological fluids while law enforcement officers are awaiting the results of a full DNA analysis. For example, a precipitin test is the type of test used to confirm that blood found at crime scenes is, in fact, human blood and not animal blood, and blood typing tests can quickly categorize the blood type of the specimen, which can be used to rule out suspects or victims whose blood type doesn’t match the sample.
Where Do Forensic Serologists Work?
Like their fellow forensic specialists, forensic serologists spend most of their time in a lab, analyzing samples and applying the methods of forensic science and, more specifically, forensic serology.
Many forensic serologists work in law enforcement agencies of some kind. A forensic serologist may find employment opportunities in crime scene investigation units in larger state, county and local police departments. Federal government law enforcement agencies like the Federal Bureau of Investigation (FBI) and the Naval Criminal Investigative Service (NCIS) also employ forensic serologists.
Not all forensic serologists work in law enforcement agencies directly, even though their work supports criminal investigations. Instead, forensic serologists may work in the office of a medical examiner or district attorney.
Independent laboratories may also employ forensic serologists, as well as other types of forensic science technicians. Law enforcement agencies that don’t have a dedicated forensic serologist may outsource the testing of specimens obtained from crime scenes to these laboratories.
Forensic Serologists vs. Crime Scene Investigators
A common question from students interested in criminal justice and forensics is how forensic serologists compare to crime scene investigators. Both forensic serologists and CSIs are practitioners in the forensic sciences. While forensic serologists are specialists in the use of serology methods for forensic investigation, crime scene investigators are typically generalists, according to the Bureau of Labor Statistics (BLS).
When it comes to the actual work performed, forensic serologists do many of the same duties as crime scene investigators, only focusing on the identification of bodily fluids. Like CSIs, forensic serologists spend some time in the field, gathering samples of evidence at crime scenes, National University reported. Much of their work is performed in the lab.
Forensic Serologists vs. Forensic Pathologists
There are many types of forensic specialist careers. Forensic pathologist is one career commonly confused with serologist.
While Serologists examine samples that contain (or may contain) bodily fluids, a forensic pathologist, or medical examiner, is the professional who performs an autopsy on the body of the deceased.
The Education Needed for a Forensic Serologist
Most forensic science technicians, including serologists, need at least a bachelor’s degree and on-the-job training to work in this role. New forensic science technicians most commonly learn the specific laboratory techniques needed for an area of specialty, like forensic serology, on the job, according to the Bureau of Labor Statistics. However, an aspiring forensic serologist can pursue formal education in serology and related areas through certificate programs and master’s-level degree programs.
Undergraduate Degrees for Forensic Serologists
If you want to become a forensic serologist, you will need at least a bachelor’s degree in a science-related field. Forensic science is a popular undergraduate degree for aspiring serologists and crime scene investigators. Majoring in general biology or one of the physical sciences, such as chemistry or physics, can also put you on the path to a forensic serologist career.
Alternatively, some students start out their careers earning an undergraduate degree in a field like criminal justice or law enforcement and then study forensic sciences at a higher level of education, such as a certificate or graduate-level degree program. If you choose this route, you need to make sure that you complete enough science coursework to meet the prerequisites for a forensic sciences program in the future. You can do this by either selecting a criminal justice bachelor’s degree program that offers a forensic science concentration or taking extra coursework – perhaps even a minor – in biology or chemistry.
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Graduate Certificate Options to Become a Forensic Serologist
A master’s level of education isn’t a strict requirement for forensic science technicians, but you may still feel that you need to advance your education in more formal ways than on-the-job training. A certificate program may offer a good middle-ground solution.
At the certificate level, as at the bachelor’s level, most programs cover a broader curriculum in forensics and forensic sciences. For example, students seeking a forensic science certificate from George Mason University may take courses in the foundations of forensic science methods and their applications, techniques for basic crime analysis, concepts for trace and physical evidence, toxicology, fingerprint identification and DNA analysis principles and systems.
Madonna University offers a DNA analysis certificate that includes courses in genetics, molecular and forensic biology, biochemistry, and probability and statistics.
The University of Florida‘s Forensic DNA & Serology certificate program includes studies in biological evidence and serology, forensic DNA analysis, blood distribution and spatter and laboratory quality assurance and quality control procedures.
Master’s Degrees and Beyond
The graduate level is where students can seek out degree programs in serology specifically.
For example, the University of Florida Health offers an online Master’s Degree in Forensic DNA & Serology with a curriculum created to align with the FBI National Standards educational requirements for DNA Technical Leaders and Supervisors. This degree program is offered through the university’s College of Pharmacy and technically awards a Master of Science in Pharmacy degree with a concentration in Forensic DNA & Serology.
Students in this graduate degree program can expect to take courses in biological evidence and serology, the theory and practice of forensic DNA analysis, forensic genetics, forensic immunology, blood distribution and spatter interpretation and the principles of quality assurance and quality control in analytical chemical laboratory settings. The forensics coursework builds upon a foundation in science and statistics, including core courses in mammalian molecular biology, metabolic biochemistry, the principles of nucleotide activity and applied statistics for data analysis.
Rutgers University is another institution that offers formal study in forensic serology and related fields. In the school’s Master of Science in Forensic Science, Biochemistry/Biology Track degree program, students complete both lecture and laboratory coursework in forensic serology. Other core courses in this program include forensic DNA laboratory procedures, forensic trace evidence, forensic pattern evidence, forensic toxicology, forensic and analytical molecular biology, forensic science research methods and forensic theory and policy.
If you want to work in high-level research or advance to a management role as a senior forensic serologist or chief serologist of a crime lab, you may need an even higher level of education, such as a Doctor of Philosophy (PhD) or medical doctorate (Doctor of Medicine or Doctor of Osteopathic Medicine) degree.
Studying Forensic Science
For students who major in forensic science as undergraduates, courses in biology and chemistry make up much of the curriculum. In one of these programs, you might expect to study human biology, human anatomy and physiology, molecular and cell biology, genetics, microbiology, organic chemistry, experimental chemistry and analytical chemistry.
Other coursework focuses on the forensic application of these sciences through investigative and evidence handling procedures and laboratory techniques. Students are likely to study the fundamental practices of forensic science, criminalistics, crime scene investigation, criminal law and procedure and courtroom proceedings. Students may have the opportunity to take courses in serology and body fluid and DNA analysis specifically, as well as in specialty areas like firearms and tool mark analysis.
Forensic science degrees typically cover an interdisciplinary curriculum that encompasses the sciences of biology, chemistry and physics, as well as criminal investigation and criminal justice procedures. Some schools offer bachelor’s degrees in forensic techniques and applications of specific disciplines of science. For example, the University of Texas at El Paso offers majors in both forensic biology and forensic chemistry.
Because biological fluids are potentially dangerous substances, students of forensic science need to learn general safety protocols to follow when collecting, analyzing and otherwise handling evidence. Many forensic serologists degree programs focus on proper evidence handling methods, which include safety protocols for when practitioners encounter environmental hazards and methods of collecting and storing potentially dangerous substances that can serve as evidence.