Scientists have studied bloodstain patterns since at least the late nineteenth century. Modern forensic science employs a mix of technology, as well as scientific and mathematical knowledge to solve all types of violent crimes, from assault to first-degree murder. Blood spatter analysts play a vital role in determining the step-by-step events of violent crimes. To become a blood spatter analyst, you must earn an education and complete rigorous training. Although the forensic science field employs a relatively small number of people, heavy crime caseloads and advancements in technology promise to offer many new opportunities in blood forensics.
What Does a Blood Spatter Analyst do?
Blood spatter analysts – more commonly referred to as bloodstain pattern analysts – work in forensic science teams that support criminal investigations. More specifically, they analyze bloodstain patterns to reconstruct the events of a crime.
When forensic scientists investigate a crime scene, they collect evidence that may relate to the method and manner in which the crime occurred. They examine and collect materials such as carpeting, fibers, clothing, weapons and other objects that can yield clues to solve the crime. They also take photographs, create molds of impressions such as footprints and collect samples of blood or other bodily fluids within the crime scene.
Bloodstain pattern analysts do what their title implies; they analyze the bloodstain patterns related to the crime. At the crime scene, they measure the distance between the victim and blood spatter patterns that surround the victim. They take note of the location and number of bloodstains and examine the patterns of each stain. Oftentimes, blood spatter analysts continue their analysis in the laboratory using photographs taken at the crime scene.
By analyzing the location, size, shape and amount of blood in a crime scene, bloodstain pattern analysts can often determine the location of the victim at the time of the scene, along with the position and height of the weapon used to assault or kill the victim. They can determine the direction from which the weapon caused the impact and the sequence of events related to the crime. For example, if a victim suffered multiple gunshot wounds, the bloodstain pattern analysts would try to determine where the victim stood or sat when the bullets struck him, the position of the perpetrator, the position of the weapon and the type of weapon used.
The expertise of blood spatter analysts help solve many crimes. Sometimes, investigators cannot find the crime weapon, and may not know exactly what type of weapon the perpetrator used. Oftentimes, bloodstain pattern analysts can assist in determining the likely weapon by conducting tests that measure how various weapons produce bloodstain patterns. Experienced bloodstain pattern analysts become experts on determining the difference between blood spatter from a gunshot, knifing or bludgeoning crime.
In testing, a bloodstain pattern analyst might reconstruct a crime scene to determine the trajectory of a bullet and the bloodstain patterns the impact of the projectile would create. Analysts apply complex calculations to account for factors such gravity, velocity and drag in order to determine the nature of a bloodstain pattern.
Bloodstain evidence comes in many forms. Some crime scenes have large amounts of blood, while others have very little. Some crime scenes contain other bodily fluids, such as semen. As with blood, analysts can collect semen, test it for DNA and examine its pattern to determine the events of the crime.
Blood spatter analysts use a variety of equipment and instruments to document crime scenes, including digital cameras, 3D scanners, scales, levels, magnifying loops, tape measures, markers, protractors and scientific calculators. After analyzing the evidence in the laboratory, they painstakingly document each piece of evidence, before sealing them in bags and storing them for later testing or presentation in court.
Oftentimes, bloodstain pattern analysts must appear in court to testify about the crime scenes they processed and the conclusions of their analysis. They must have good written and verbal communication skills to careful document their findings and explain complex scientific concepts to laymen.
Bloodstain pattern analysts often work irregular hours. Oftentimes, they must attend crime scenes on nights, weekend or holidays. Some bloodstain pattern analysts work exclusively in laboratories, operated by government agencies or private forensic science companies. A crime lab analyst often works regular business hours.
How Does One Become a Blood Spatter Analyst?
Becoming a blood spatter analyst requires a combination of education and training. Most bloodstain pattern analysts have at least an associate’s degree from a community college or a bachelor’s degree from a college or university. Employers who seek analysts with bachelor’s degrees often prefer candidates who hold degrees in criminal justice or forensic science.
Forensic science coursework often includes classes in trigonometry, criminology, biology, statistical analysis, anatomy, physics, mathematics and constitutional law. Some employers accept blood spatter analyst candidates who have degrees in a natural science such as biology or chemistry.
The American Academy of Forensic Science maintains a list of community colleges, four-year colleges and universities that offer forensic science degree programs. You can find forensic science programs in most states, at educational institutions such as the University of Alabama Birmingham, Austin Peay State University, California State University Long Beach, Boston University School of Medicine and Defiance College. Some schools conduct certificate programs, while others offer bachelor’s and master’s degrees. Many college forensics programs enable students to concentrate in a particular area such as DNA, toxicology or pathology.
In some jurisdictions, forensic science investigators are sworn police officers, which requires them to attend a police academy.
What Training Is Needed to Become a Blood Spatter Analyst?
After earning a degree, you must receive on-the-job forensic training before you can work as a bloodstain pattern analyst. Oftentimes, trainees can complete their training in about one year. Typically, trainees work closely with experienced investigators, who teach them the fine details of bloodstain pattern analysis. Training may include laboratory work and crime scene investigation. Throughout their careers, blood spatter analysts must continue their education to stay abreast of new technologies and crime scene investigative methods.
The Federal Bureau of Investigation’s (FBI) Scientific Working Group on Bloodstain Pattern Analysis (SWGSTAIN) established guidelines for bloodstain pattern analysis trainees, which many law enforcement agencies follow when hiring new analysts. The SWGSTAIN guidelines encompass education, training, knowledge and skills. SWGSTAIN outlines requirements for mentorships programs and competency testing that bloodstain pattern analysts must complete before they can practice their trade. To qualify for bloodstain pattern analysis training, a candidate must meet numerous requirements.
A candidate must have an associate’s or bachelor’s degree in a discipline related to the bloodstain pattern analysis field such as biology, forensic science or chemistry. High school graduates may qualify, if they have at least four years of experience as a criminalist, homicide investigator or crime scene technician.
A trainee must work with a mentor during training. The mentor must ensure that the trainee follows the SWGSTAIN curriculum, and he or she must evaluate the trainee’s work. The length of a training program can vary, depending on the trainee’s progress. At the end of the training program, trainees must pass a competency test.
In addition to the examination, a trainee must prove her proficiency in areas related to bloodstain pattern analysis, including an understanding of safety issues involving blood and the use of biohazard equipment. She must understand the scientific principles of bloodstain pattern analysis, and have knowledge of its history.
A trainee must have an expert understanding of the laws of physics as they relate to gravity, surface tension, viscosity, velocity and air resistance. He must prove his ability to analyze data, identify problems, collect data and form a hypothesis.
The trainee must understand how environmental factors can contribute to bloodstain patterns, including temperature, animal activity, airflow, substrate characteristics and humidity. She also must understand the physics of blood in motion, including wave castoff, flight paths, oscillation, drop formation and kinetic energy.
Additionally, a trainee must demonstrate proficiency in documenting crime scenes using notes, photography and sketches.
Trainees must understand certain human biological factors such as types of bloodletting injuries and the types of bloodstains they can form. A trainee must demonstrate an ability to recreate a bloodletting event in a controlled setting such a laboratory. He must understand the limits of bloodstain pattern analysis and how to communicate conclusions of his investigation.
The trainee must pass the competency test before she can work independently. Some mentors choose to test trainees throughout the training course, allowing them to work independently in areas they have proven competent.
After passing the training course, a SWGSTAIN-qualified bloodstain pattern analyst must take at least eight hours of continuing education each year.
Do Blood Spatter Analysts Need a License or Certification?
SWGSTAIN guidelines recommend that blood spatter analysts join a professional organization. Many professional organizations offer certification programs, many of which provide continuing education. Licensing and certification requirements vary by state. Many bloodstain pattern analysts choose to earn certification to add credibility to their careers and to periodically continue their training.
Many forensics associations only certify bloodstain pattern analysts who meet all SWGSTAIN requirements, along with their own qualifications. For instance, the International Association for Identification certifies SWGSTAIN-qualified analysts who have completed at least 240 hours of training. Of the 240 training hours, an applicant must have completed at least 40 hours in bloodstain pattern analysis coursework, as well as training in areas such as blood detection techniques, forensic science, evidence recovery, crime investigation and forensic photography.
Some industry organizations offer training and certification in specify areas of bloodstain pattern analysis. For example, the International Association of Bloodstain Pattern Analysis offers certification courses in visualization of latent bloodstains, bloodstain analysis on textiles and advanced bloodstain pattern analysis.
Some professional associations conduct seminars and workshops throughout the year that cover a wide range of forensic science topics. For instance, the Association for Crime Scene Reconstruction conducts seminars on documenting bloodstain patterns from shooting incidents and investigating officer-involved shootings.
How Much Does a Blood Spatter Analyst Make?
The U.S. Bureau of Labor Statistics (BLS), a government agency that tracks American jobs, does not provide information specific to the blood spatter analyst profession. However, the BLS estimates that forensic science technicians as a whole earned a median salary of around $58,000 in 2017. The median salary represents the middle of the forensic science technician pay scale.
Top earners took home nearly $96,000, while technicians at the bottom of the pay scale made around $34,000. Testing laboratories paid the highest salaries, followed by state and local governments.
What Are the Job Prospects for Blood Spatter Analysts?
The BLS does not provide job outlook data specific to bloodstain pattern analysts. However, the Bureau expects jobs for all forensics science technicians to increase by around 17 percent, from now until 2026. Although the field will experience a high growth rate, it is a relatively small profession. The actual number of new jobs available probably will not exceed 2,600.
High crime rates may prompt state and local agencies to beef up their forensics staffs. Technological advances promise to make forensic science results more valuable in criminal cases, which may boost the job outlook for all forensic science technicians.