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CHAPTER 8. HAIR. TRACE EVIDENCE. Hair and Fiber. Colin Ross- 1921 Australia. A 13 year old girl wrapped in a blanket had been raped,strangled and beaten. She was left wrapped in a blanket on the ground. But no blood was found- she had been washed and dried before being left.
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CHAPTER 8 HAIR
TRACE EVIDENCE Hair and Fiber
Colin Ross- 1921 Australia • A 13 year old girl wrapped in a blanket had been raped,strangled and beaten. She was left wrapped in a blanket on the ground. But no blood was found- she had been washed and dried before being left. • A local bar owner admitted the girl was at his bar that night. • Two blankets in his home were analyzed. A 12+ inch strand of reddish-blond hair was found. It had been forcibly removed. • At trial the crime scene hair was distinguishable from other patrons of the bar. He was convicted and hanged.
John Fiorenza- 1936 NYCFibers • Nancy Titterton,wife of an NBC executive was found face down in an empty bathtub, raped and strangled with her own pajama jacket. The apartment showed signs of a struggle. She also had ropes about her wrists and a lone, stiff white hair was located with it. • The rope was traced to its manufacturer in Pennsylvania- and sold to the upholsterer who employed Fiorenza and who worked on the horse hair sofa in the victim’s home. • He confessed when confronted with the fiber evidence. Fiorenza was convicted and executed.
Samuel Morgan- 1940 England • Mary Hagan, 15, went for a paper and never returned. She had been raped and strangled and left by the railroad. A muddy, bloodstained finger bandage was left at the scene. She had a bloody thumbprint on her neck. • The bandage had a disinfectant that was used by the military. Sam Morgan had deserted the military recently and was suspected in an earlier attack on another woman. When he was detained his thumb was still injured. • The bandage was common- military issue- but it was also stitched by hand. That was the single detail that convicted him. • He confessed, recanted, re-confessed, was convicted and hanged.
John Vollman-1958, Canada Hair • Gaetane Bouchard was found in a gravel pit near a ‘lover’s lane’ area in Edmundston, Canada. She had been stabbed and left for dead. Also found were a few small green flakes of paint, probably from a car. • Gaetane had met John Vollman earlier and had dated him for a time. Friends reported seeing them together the night she went missing. They were in his green 1952 Pontiac. • The paint chips matched John’s car, but he admitted to parking with Gaetane. • Also found was a single strand of hair clutched in the dead girl’s hand. • A new technique, NAA, was used to identify the hair and link it to John Vollman. • He was convicted.
Wayne Williams- 1981 Atlanta Fibers From October 1979 to May 1981, Wayne Williams killed twenty-seven young black boys in Atlanta. As most serial killers are white, it was thought that the Atlanta child murderer was a white racist. Most of the boys were taken from black neighborhoods where a white man would stand out, so police announced that they were looking for a probable black serial killer.
Wayne Williams • On 22 May 1981 at 2 AM, police heard someone dumping something in the Chattahoochee river. A black man, 22-year-old Wayne Williams, was found climbing into a station wagon, and was questioned by police then allowed to go. • When a body (Nathaniel Cater) turned up in the river a week later police talked to Williams again. Fibers found on the victim matched one's found in William's car and he was arrested. At trial Williams was found guilty and sentenced to life imprisonment. • Yellow green fibers had been found on several of the victim’s bodies.
Wayne Williams The fibers were manufactured by the Wellman Corp and sold during 1967-74 and sold undyed to other companies. West Point Pepperell Corp, of Georgia, made Luxaire carpet in English Olive green- only between 1970-1971, That kind of carpet was found in Wayne William’s bedroom.
Wayne Williams- The Statistics • Only about 16,000 yd2 were sold (out of 16 billion yd2 total) only 82 homes in Georgia should have that same carpet, ten years later. The odds were 1 in 7,792 now. • BUT, Jimmy Ray Payne (killed a month earlier) had fibers that also matched carpets in the Williams’ car! This was a 1 in 3828 odds. • SO- the odds of both fibers found on victims matching Wayne Williams’ carpeting was 1 in 30 million!
Jeffrey MacDonald-1970, NCFiber, hair Fort Bragg, North Carolina saw the murder of two small girls, and a young pregnant mother. The Green Beret father and husband was knocked out and stabbed in the mid-chest. His wounds were minor and he gave a detailed account of Manson-like hippies attacking him and his family. Because he was a physician he tried to ‘save’ his family when he came to.
Jeffrey MacDonald • The living room was ‘messed up’ in the struggle. • “Pig’ was written in blood in the master bedroom. • Both girls and their mother were multiply stabbed by an ice pick. • Each of the victims had a different blood group- so their movements could be traced. MacDonald’s blood was limited. • Jeffrey draped his blue pajama top over her body after he found his wife stabbed 21 times. • Blue fibers were found in each of the victim’s rooms. • The 48 holes in the pajama top were all smooth and round. • MacDonald was convicted, but released on appeal. He is now serving three life sentences.
Introduction Trace Evidence--any small pieces of material, man-made or naturally occurring (animal, plant or mineral) Most common examples: • Hair • Fiber
Test Questions for Trace Evidence • What is it? • Is it man-made or natural? • What is its source? • How common is it? • Can it be identified to a single source?
Hair Human hair is one of the most frequently found pieces of evidence at the scene of a violent crime. It can provide a link between the criminal and the act. From hair one can determine: • Human or animal origin • Race • Body region • Manner in which hair was removed • Treated hair • Drugs ingested • BUT NOT- age or sex of origin The age of an individual cannot be determined definitively by a microscopic examination; however, the microscopic appearance of certain human hairs, such as those of infants and elderly individuals, may provide a general indication of age. The hairs of infants, for example, are generally finer and less distinctive in microscopic appearance. As individuals age, hair can undergo pigment loss and changes in the configuration of the hair shaft to become much finer and more variable in diameter.
Removal of Hair Naturally shed When hairs originate from a body in a state of decomposition, a dark band may appear near the root of the hair. This characteristic has been labeled a postmortem root band. Forcibly removed Forcibly removed with root tissue DNA test can be done
Hair Stages • Hair goes through phases- growth, resting, and dying/loss. 80-90% 2% 10-18% The average period of growth for scalp hair is approximately 1,000 days; the resting phase lasts about 100 days. Approximately 10 percent of the hairs on a human head (100/1000), therefore, are in the quiescent telogen phase, and a minimal amount of force—such as that from combing—is required to dislodge the hairs from the dormant follicle.
Hair Growth • Terminology • Anagen--hair that is growing • Catagen--hair at rest • Telogen--hair that is dying • Length--00.5 mm per day or 1 centimeter per month; approximately one half to one inch per month
MORPHOLOGY OF HAIR • Hair is often found as PE at a crime scene • Hair cannot be individualized yet • (unless DNA is present in root ball/follicular tag) • Must be properly collected and can then, be used as corroborative evidence • Hair is an appendage of the skin, and grows out from a HAIR FOLLICLE • Parts of hair are: root (or bulb), shaft, and tip end • Shaft has 3 layers- cuticle, cortex, and medulla
Hair MorphologyThe Study of Structure and Form Parts of the hair • Shaft--part of the hair that sticks out of the skin • Tip – end point of hair shaft • Root--lies below the epidermis • Follicle--structure from which the hair grows
THE CUTICLE • 2 characteristics that make hair good evidence are- 1) resistance to chemical decomposition and 2) ability to retain structural features over long period of time • These characteristics are due to the cuticle • Cuticle is formed by overlapping scales that point toward the tip end • Cuticles are formed as special cells that keratinize (harden) and flatten as they form in the follicle • Pattern of the scales are sometimes useful in determining species of animal
Mosaic Pectinate Imbricate Petal Diamond petal Chevron Hair Cuticle The cuticle is the outermost layer of hair which is covered with scales. Scales also always point toward the tip of the hair. These scales differ between species of animals and are names based on their appearance. Some of these scales are variations of the same and include:
Cuticle Patterns • Each species has different patterns. • Cannot determine the specific animal from the hair.
Scale Types Mosaic Chevron
Scale Types (cont) Pectinate Imbricate
Scale Types (cont) Diamond Petal Petal
HUMAN SCALES In order to visualize the scales • paint fingernail polish on a slide • place a hair on the polish • lift off the hair and observe the scale imprints What pattern is seen in this slide?
Human Cuticle Tip end Tip end Imbricate pattern
THE CORTEX This is the layer below the cuticle • Made up of spindle-shaped cortical cells that are parallel to the cuticle • Pigment granules here give hair its color • Color, shape, and arrangement of granules give points of comparison between individuals • Must use microscope to view the cortex
Hair Cortex The cortex gives the hair its shape. Wavy or curly hair is oval in cross section. Kinky or woolly hair is flat in cross section, Straight-textured hair is round in cross section,
THE MEDULLA • Collection of cells that run in the center of the shaft • Many animals have a prominent medulla- humans do not • Medullae vary from person to person and from hair to hair • Medullae classified as: continuous, interrupted, segmented/fragmented or absent • Humans usually have fragmented or absent medullae • Mongoloid race usually has continuous medulla • Shape of medullae are also significant- usually cylindrical in humans but can be patterned in animals
Hair Medulla The medulla is the hair core, but is not always present. The medulla comes in different types and patterns. Types: • Continuous • Intermittent or interrupted • Fragmented • Absent--not present
Hair Medulla Patterns Uniserial Multiserial Vacuolated Lattice Amorphous (without a distinct pattern)
RABBIT MEDULLA Rabbit medulla is different depending on the type (location on the rabbit) of hair. The one to the left is multiserial. The one to the right is a uniserial ladder and is found in guard hair.
HUMAN MEDULLA Human medulla may be continuous, fragmented or absent.
Determined by measuring the diameter of the medulla and dividing it by the diameter of the hair. Medullary Index Medullary Index for human hair is generally less than 1/3. For animal hair, it is usually greater than 1/2.
IDENTIFICATION AND COMPARISON OF HAIRUsing Comparison Microscope • In trials usually just identify hair as human or animal. • Identifying which human the hair belongs to is much harder. • Need many standards (samples) for comparison to suspect. • Can compare scalp or pubic hairs. • Again, probability that sample is PE from the suspect is the question in a trial.
Hairs of Caucasoid or Caucasian origin can be of fine to medium coarseness, are generally straight or wavy in appearance, and exhibit colors ranging from blonde to brown to black. The hair shafts of Caucasian hairs vary from round to oval in cross section and have fine to medium-sized, evenly distributed pigment granules. Hair and Racial OriginCaucasoid (European)
Hairs of Mongoloid or Asian origin are regularly coarse, straight, and circular in cross section, with a wider diameter than the hairs of the other racial groups. The outer layer of the hair, the cuticle, is usually significantly thicker than the cuticle of Negroid and Caucasian hairs, and the medulla, or central canal, is continuous and wide. The hair shaft, or cortex, of Mongoloid hair contains pigment granules that are generally larger in size than the pigment granules of Caucasian hairs and which often appear to be grouped in patchy areas within the shaft. Mongoloid hair can have a characteristic reddish appearance as a product of its pigment. Mongoloid (Asian)
Hairs of Negroid or African origin are regularly curly or kinky, have a flattened cross section, and can appear curly, wavy, or coiled. Negroid pigment granules are larger than those found in Mongoloid and Caucasian hair and are grouped in clumps of different sizes and shapes. The density of the pigment in the hair shaft may be so great as to make the hair opaque. A Negroid hair shaft exhibits variation or apparent variation in diameter because of its flattened nature and the manner in which it lies on the microscope slide. Twisting of the hair shaft, known as buckling, can be present, and the hair shaft frequently splits along the length. Negroid (African)
