Forensic anthropology is the application of the scientific methods and theories of physical anthropology to matters of legal concern. This specialized field focuses primarily on the analysis of human remains that are skeletonized, severely decomposed, or otherwise unidentifiable through standard medical means. The forensic anthropologist works to establish a biological profile of the deceased, providing foundational information to law enforcement and medicolegal investigators. This work applies knowledge of human biology, variation, and evolution within the framework of the justice system. The ultimate goal is to assist in the identification of the individual and to interpret the circumstances surrounding their death.
The Foundation: Analyzing Human Skeletal Remains
The primary scientific task of a forensic anthropologist is the creation of a biological profile from the recovered skeletal elements. This profile includes estimations of sex, age at death, stature, and ancestry, narrowing the pool of potential identities for the deceased. Estimating sex is often one of the most accurate determinations, relying heavily on the pelvis due to sexually dimorphic traits related to childbirth, such as a wider subpubic angle. Although the skull also displays differences, the pelvis remains the most reliable bone for this determination.
Estimating the age of an individual depends on whether the person was still growing. For immature remains, the eruption and formation of teeth provide the most accurate estimate, alongside the degree of epiphyseal fusion, where growth plates merge with the shaft of long bones. In adults, age is estimated through degenerative changes, such as the metamorphosis of the pubic symphysis or changes to the auricular surface of the pelvis. These methods rely on observing the predictable wear and tear that occurs over a lifetime.
Stature is estimated by measuring the maximum length of long bones, such as the femur or tibia, and applying these measurements to population-specific regression formulas. These calculations provide a range for the individual’s living height. Ancestry estimation, while complex, uses non-metric and metric analysis of the skull, often relying on craniometric data and multivariate statistical methods to suggest a general ancestral group.
Role in the Legal System: Trauma and Contextual Analysis
The forensic anthropologist analyzes skeletal trauma to interpret the events surrounding the time of death. Trauma is categorized based on when the injury occurred: ante-mortem (before death), peri-mortem (around the time of death), or post-mortem (after death). Ante-mortem trauma is identified by signs of healing, such as new bone formation or callus development around the injury site.
Peri-mortem trauma occurs when the bone was still “fresh” or hydrated, causing it to break with smooth, curved fracture edges. This is distinct from post-mortem damage, which occurs when the bone is dry and brittle, resulting in jagged, sharp-edged fractures. Analysis of the trauma patterns—such as the unique entry and exit wounds of projectile trauma, or the focused damage from sharp force trauma—can provide evidence about the weapon type and the sequence of events.
Taphonomy, the study of the processes affecting the remains after death, is used to estimate the Post-Mortem Interval (PMI), or time since death. This involves assessing decomposition stages, environmental factors like temperature and humidity, and the effects of scavenging animals or root growth. The anthropologist assists in the careful recovery of remains using systematic archaeological techniques to ensure all evidence is documented and collected. The interpretation of these findings, from trauma analysis to PMI estimation, is then communicated to the court by the anthropologist, who serves as an expert witness.
Distinguishing Forensic Anthropology from Related Sciences
Forensic anthropology is frequently confused with other forensic disciplines, but it occupies a distinct scientific niche. The field differs significantly from forensic pathology, which primarily concerns itself with the medical cause and manner of death by examining soft tissue and internal organs. While a pathologist handles fresh remains to determine the immediate physiological reason for death, the anthropologist is consulted when remains are skeletonized or severely decomposed.
The discipline has a relationship with forensic archaeology. Forensic archaeology focuses on the systematic location, mapping, and excavation of all physical evidence at a scene, including artifacts and the environmental context. The forensic anthropologist then takes the recovered human remains and applies osteological expertise to analyze the bones themselves. The archaeologist focuses on the “where” and “how” of the burial or scene, while the anthropologist focuses on the “who” and “what happened” to the individual.