Hair and Fiber

History of Hair and Fiber Analysis

1899- Francois Goron, a forensic scientist, was able to tell the court the victim of a murder scene who had dyed his hair before the crime took place. This important discovery led to the identity of the body and brought the case a step closer to finding the criminal. In later years forensic scientists would discover that by studying a piece of a victim you can tell whether or not metal toxicity or different types of drugs were involved.

1857- The mere idea of the scientific study of hair, trichology, was published in France. This study rapidly grew in the early 20th century after the examination of microscopic hair.

1937- The basis for hair analysis information was published written by Professor John Glaister titled "Hairs of Mammalia for the Medico-legal Aspect".

1977- The groundwork for the use of hair evidence was published written by John Hick titled "Microscopy of Hairs: A Practical Guide and Manual".

1989- Ted Bundy was executed for murder after fibers were found in his van that were consistent with a young girl’s clothing who he killed.

Fiber

The Importance of Hair and Fiber

Hair and fiber are two of the most important resources in Forensic Science and are often responsible for providing valuable clues as to the identity of an assailant or attacker.

The discovery of hair on the body of a victim or on the clothes of someone who has been the victim of an assault can often be used to determine race and sex. It can also be used to extrapolate DNA for comparison.

Although hair is classified as benign dead matter it still contains DNA even though the hair itself is not actually a living organism but is merely pushed through the follicles of the scalp, arms, legs or any other part of the anatomy where hair is found.

Fibers too are an important discovery and can go some way to determining what an attacker or killer was wearing at the time of the incident. Many forensic scientists use fibers as a means of determining the nature of the item worn and in some instances can be as precise as to identify the make of the garment and thus the manufacturer. In some instances this technique is so successful that garments that are rare or indeed specially made can be identified and thus a list of possible suspects drawn up simply by the number of units sold.

Collecting Evidence

At the crime scene hair and fiber samples are collected from the surrounding area. These samples are collected by Scenes of Crime Officers (SOCO) dressed in protective clothing so that their own clothing and hair doesn’t contaminate the evidence. These samples are collected in sealed containers to prevent cross contamination. The victim's clothing may be examined for hairs and fibers that don’t match their hair and the fibers they’re wearing. Hair and fibers are also collected at the autopsy when the pathologist will scrape the underside of the victim's fingernails for any hair, skin, fibers or material that might have gathered there from the victim possibly scratching their attacker in the process. These materials are then collected and stored so further examination and comparison may take place later.

Types

Wool




Natural

Natural fibers are hair-like materials that are able to be spun into thread or rope. Examples of natural fibers are silk, wool, and cotton.

Synthetic

Polyester

Synthetic fibers are created by forcing fiber forming materials through holes to form a thread. A few examples of synthetic fibers are polyester, nylon, and acrylic fiber.

Hair Analysis

Analyzing a hair sample can conclude whether it’s animal or human. Through examination of a human hair, scientists can determine the person’s race, where on the body the hair came from, how the hair was removed, alteration of the hair, and damage done to the hair.

Fiber Analysis

Fiber samples allow scientists to identify whether the sample is natural or synthetic. Once identified, the fiber can be compared to fibers from the victim, a suspect's clothing, a vehicle's interior, or the fabric in a carpet.  

Reliability

Hair samples can’t always serve as a definite source identification, but are very useful for closing in on a group of suspects.

Labeled Hair Diagram

Famous Case

A serial killer named Ted Bundy was responsible for over 30 deaths, but with a lack of physical evidence to prove him guilty to the claims when he was arrested in 1975. Two years later Bundy was accused of kidnapping and was prepared to stand trial for murder in Colorado, but he fled to Florida where he killed 3 more people in 1978. He was captured in February during the same year due to the physical evidence. With conviction of another murder, 12 year old Kimberly Leach, fibers were found in Bundy’s van that matched the young girl’s clothing. Ted Bundy was executed in the electric chair in 1989.