How Forensic Anthropologists Determine Height

Forensic anthropology has a very important role in forensic science--specifically in identifying human remains. Determining how tall a person was in life is one important part of the identification process. Here I will briefly explain the most common methods forensic anthropologists use to determine stature.

Consider this scenario:

Human remains have been found in a field and a forensic anthropologist has been called out to help the investigation. When the anthropologist arrives, she finds that many of the bones are missing--they have likely been carried away by coyotes or some other scavenger. The only bones visible are a few ribs, several vertebrae, part of a femur, and pelvic bones.

Although only these few bones have been found, the forensic anthropologist believes she will be able to determine, with reasonable accuracy and within a reasonable range, the sex, height, and perhaps even the age of this individual.

She has this confidence because she knows that stature can be determined with reasonable accuracy via the long bones (long bones include the leg bones and arm bones) and especially the femur. She is glad that the pelvis is available because that will make it easier to determine sex-and sex, along with race and (sometimes) age, is factored into the equation for height. The length of the femur relative to height differs slightly depending on sex, race and age (if the decedent is determined to be approximately 40+ years old).

Although determining height would be easier if she had the complete femur, other forensic anthropologists (Steele, McKern) before her have created a formula for determining the complete length of the femur when only a partial femur is present. She will use that formula and then will apply the usual equation for determining height.

In general, a person's height approximately = femur height times 2 & 2/3. However, as I stated earlier, sex, race, and age also play a role in determining stature. In the resources section of this article, I've included a link to formulas used to determine stature.

If the femur had not been present she may have used the vertebrae to determine stature. Statistical data and equations are available (thanks to the hard work of many forensic scientists) for many other bones of the body.

As I've already stated, another factor in estimating height is age. A forensic anthropologist estimates age and will add relevant age data to the formula for height estimation. If the bones are of a child, estimating height will be more difficult (because in children the bones are not fully fused and the equations used are for fused (ossified) bones only).

Also, age is important to the equation because people begin losing a bit of height in their 30's or 40's. If the decedent is estimated to be an older individual, this should be added to the equation in order to get a more accurate stature estimate. Advances in forensic science technology will likely refine this and will help make identification easier.

Along with measuring the femur in order to determine height, the forensic anthropologist will study the femur to get an idea of the general build of the person. Muscles attach to bone and exert a force on the bone itself. This force creates tell-tale ridges on the bone. The more muscular a person is, the more prominent these ridges. Through this study, the forensic anthropologist will get an even better picture of what the individual looked like in life.

The estimated height, along with sex, age, race and general build are all important elements of identification. While the forensic anthropologist may not always be able to supply more than these characteristics of the decedent, these characteristics at least narrow down the possibilities.

Note: Forensic anthropology, and all of forensic science, is a large and complex field. This article is far from being all-inclusive. Many different bones can be used to determine height. Furthermore, all areas within forensic science are advancing rapidly as new technology develops. It is difficult to predict how forensic science methods may change in the next decade, but I believe there will be many changes.

If you are interested in reading more about forensic science, the following articles may interest you:

Forensic Science and Teeth

What Forensic anthropologists can learn from the Pelvic bones

Secrets of the Skull

Inside The Forensic Anthropology Lab