Stanford Johnson was found dead in the home he shared with his son, Terrence Johnson. An autopsy later revealed that the victim was killed by manual strangulation. Because there was no evidence that the victim's home was entered forcibly, Terrence Johnson immediately became a suspect in the investigation of his father's murder.
At trial, witnesses testified that the cuts and bruises the medical examiner observed on Terrence Johnson had not been there the day before the murder. Still other witnesses contradicted Terrence Johnson's statements that he was not home the entire evening before he called the Jefferson County emergency service to report his discovery of his father's body. Perhaps most convincing, however, was the physical evidence: A blood spot found on the victim's clothing matched Terrence Johnson's relatively rare blood type, and hairs found in the victim's hands had the same characteristics as hair samples taken from Terrence Johnson's head. The murder suspect moved to suppress the testimony of the serologist who made the connection between the hair in Stanford Johnson's hands and the hair on Terrence Johnson's head. The trial court overruled that motion.
Frye Yes, Daubert No
Sentenced to a lifetime prison term for his father's strangulation, Terrence Johnson appealed, arguing that, among other things, the court should have suppressed the testimony of the hair analysis expert. Johnson primarily relied on Williamson v. Reynolds, 904 F. Supp. 1529 (1995), a case in which a federal district judge in Oklahoma concluded that hair analysis by microscopic comparison, which may have satisfied the test established in Fyre v. United States, 54 App. D.C. 46 (D.C. Cir. 1923), did not satisfy the test of reliability established in Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579 (1993).
The Supreme Court of Kentucky took judicial notice (that is, accepted as true) the state's assertion that hair analysis is scientifically reliable “based upon the overwhelming acceptance of this evidence by other jurisdictions, as well as our own history of routine admission of this evidence at trial.” The Court further held that the Appellant could still convince the Court that the trial court erred when it admitted the serologist's testimony, however, by proving that hair analysis is no longer deemed reliable.
The opinion in Williamson was virtually the only evidence submitted by Appellant in support of his contention that hair analysis is unreliable. Finding that the case was reversed by its own appellate court and was “thus stripped of any precedential value,” the Supreme Court of Kentucky sustained Terrence Johnson's conviction.
| David L. Exline Forensic Scientist ChemIcon Inc. |
What Can Be Learned from Hair
- Human or animal?
- Race.
- Body area of origin.
- Shed or forcibly removed.
- Disease.
- Comparison to known samples.
Exline: Human hair examination and comparisons were first utilized in the early 20th century and remain the foundation of today's hair examiners. In contemporary forensic science, the value of optical hair examinations has been questioned in comparison to methods that utilize high tech instrumentation and newer analytical and statistical methods. However, hair examination is a vital part of any complete forensic laboratory.
Initially, when a sample is recovered from physical evidence or is submitted to the laboratory for examination, it is important to determine whether it is actually a hair. If it is, whether the hair is that of a human or an animal also must be determined. This is easily accomplished by looking at characteristics such as scale patterns, medulla type, color and hair morphology. When the sample has been characterized as human hair, the racial origin and body area are determined. This is an important step because only hairs from the same body region should be compared.
Valuable information can be gained in the characterization step of hair to aid criminal investigations. The racial origin of a hair can direct an investigation whose racial makeup of the assailant is unknown. Other characteristics that can be determined are cosmetic treatments to the hair, naturally shed versus forcibly removed hairs, disease, and other environmental influences.
Can’t Beat the Real Thing
A comparison of the questioned hair or hairs is another type of analysis that can be conducted. This is accomplished by comparing the questioned hair(s) to known exemplars submitted for comparison. The comparison is done using a comparison microscope—two optical microscopes connected by an optical bridge. This microscope allows the examiner to compare a questioned and known hair simultaneously in a side-by-side examination. Numerous characteristics such as color, diameter, length, morphology, root morphology, tip morphology, cortical characteristics (e.g., pigment color, pigment size and distribution, medulla type, presence or absence of cortical fusi and their distribution, ovoid bodies and other characteristics in the cortex of the hair), cuticle characteristics (e.g., thickness, size, separation, color and pigment distribution) and other microscopic characteristics of the hair are compared.
Questioned hairs are compared with known hairs from root to tip. If the examiner concludes that all the characteristics in the questioned hair are present in the known standard, corresponding directly to the specific regions of the hair shafts along the entire lengths of the hairs, a positive conclusion can be reached. When a positive hair association is made, a conclusion such as, “the question hair(s) could have originated from the known source,” is then stated.
Not All Hair Is the Same
The collection of known standards is an important factor when dealing with hair comparisons. Both plucked and combed hairs should be collected from various regions of the head or pubic regions. This is necessary due to the inherent variations found within a single subjects hair. Known standards from other people who were present at a specific location should be submitted along with the suspect and victims hairs for elimination purposes (alibi samples). Another factor to consider when dealing with known exemplars is the time of collection. Hairs may change over time. As hairs grow and naturally shed, the characteristics of the hair may change over a period of time, depending on the specific body origin and environmental influences.
The value of a hair comparison is dependent on the education, experience and training of the examiner performing the analysis. It is this experience that allows the examiner to understand the various factors that add or detract from the significance of a hair comparison.
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