Scientific Method & Evidence
When evidence is presented in the courtroom, it must face severe scrutiny by all sides in a trial. This scrutiny has been defined by previous court decisions regarding what is considered valid evidence or forensics that can be used in trial courts. These decisions have confirmed that regardless of the type of evidence presented, any analysis or conclusive results are given in court regarding findings on the evidence must come from the scientific method.
The first written court decision came in 1923 from the Frye v. The United States. An update to this decision came in 1975 the decision was passed down to use Rule 702, giving some authority to review the validity of evidence to the judge. In later years this ruling has been updated by the Daubert Standard, named such from the 1993 case Daubert v. Merrell Dow Pharmaceuticals, Inc., this standard keeps Rule 702 but also helps add more definition. The main goals of these decisions are that any forensics that is processed for analysis and presented to trial courtrooms as evidence should be based in science, and follow the scientific method to achieve results. Conclusions must be validated and accepted in a variety of ways. These validations or views of accepted science can be from known, accepted standards or numerous professional peer reviews.
Hair Analysis: The Basics
"It's a match!" We all hold our breath during crime and mystery movies awaiting those words coming out at just the right moment. It is much like the game of Clue. It was the candlestick in the library, and now, we have matched a suspect's hair to the hair on the sofa. What were the chances?
Indeed, forensic hair analysis was once a go-to for solving crime and providing proof in the courtroom. It has been a standard scene since the 1950s. Today, it is only suitable for television drama. Hair analysis, even by the top FBI crime labs, has all but been debunked.
There are different types of hair analysis, so it does continue as a valid means of research. Certain hairs may contain a root or other cells on which DNA testing can be done. Under these circumstances, a hair DNA test result is compared to the suspect's DNA, and this is conclusive science. Here is a case in which it is possible to match the hair to another human being with certainty.
Another type of hair analysis, which is also used in courtrooms as evidence, does not require a 'match.' The hair is removed from the person's head, labeled, and sent to the lab. There is no question as to whom the hair belongs. The type of testing can be to determine the past history of drug use or even can show environmental factors. These types of hair evidence are generally used when there is a chance that someone facing the judge may try to hide or lie about their use of illicit drugs. These results can indicate more than a urine screen. A urine screen can tell what may currently be in the system, or what has been used in the last 24-72 hours, in most cases. However, a drug analysis done on hair can tell much more, like the type of substances used as well as how often. The results can show the judge a behavioral pattern with the history of use up to three months before testing. The results for environmental exposures can be similar.
Forensic hair analysis for establishing the identity of a suspect in a crime scene is entirely different. Since the 1950s it has been used in courtrooms as a source of scientific certainty to identify murderers, rapists, and other criminals and sentence them to long periods in prison, sometimes life and the death penalty.
Scientists, in a lab setting, strands of hair are mounted on a microscopic slide and examined in detail. Forensic scientists compare the hair found at the crime scene to hair from the suspect. Distinguishing features are looked at, such as the color, pigment depth, thickness, and textures. From this study, these forensic scientists have presented to court judges and juries that this is evidence that it identifies a specific individual as the defining suspect in the case. Many FBI agents have even testified that the results mean that it identifies the suspect, and the results prove it to 1 in 10,000 people. Judges and juries alike, have accepted these testimonies as scientific truth and have decided that individuals were guilty of the crime in question.
Today, the FBI admits that it is not science at all. No "uniform standard" exists in the study of matching hairs. Scientists have yet to determine the precise number of hair characteristics to know the certainty of a match. The numbers that are thrown out in court testimony over the years of the matches being "1 in 10,000" was utterly false. No one really knows, and the idea that nearly 25% of the planet has the same hair structure, how can there be a scientific measurement designating a match of any kind?
The elite FBI crime laboratory has been under federal investigation since 2012. For years, their scientists have been overstating the validity of hair matches in trials. The problem is that when a scientist presents their findings as truth to a jury, a jury of the peers which are everyday people selected from the community, they do not have the background to understand that what is presented to them is exaggerated. There may be other evidence presented at the trial, but when the jury hears the hair match as truth, they may base their conviction on that single piece of evidence. Facts show that many of these cases, the person who was convicted solely on identification by hair analysis, were declared guilty and later found innocent.
Innocent People Convicted by Junk Science
Decades have passed while the FBI has used junk science results that they pushed upon unsuspecting courts, judges, and juries. Many individuals have been wrongfully convicted based on these findings. In 2009, there was a push to change the position of these types of sciences presented in court, as well as prove the innocence of these individuals.
In 2009, when confronted by the fact that the science behind the analysis of many types of forensic matching was junk, the FBI still wanted to hold on to some of its background and abilities to analyze results. The only thing pressing to the FBI seems to be getting a conviction, and not getting to the truth.
Many individuals are now facing hard work of appealing convictions, waiting for acceptance by pro-bono attorneys. However, according to the research by Tim Cushing, "the damage has been done, and the FBI's belated recognition of its contribution to the farce that is our criminal justice system isn't going to give back years of wrongfully-obtained lives." He is right. There is no way to give back years of someone's life that is wrongfully taken.
The FBI has acknowledged that they sent out experts to testify in courts for decades that overstated the findings. It was not just in one or two instances; it was nearly every forensic scientist sent out to testify in trials. In other words, they lied.
Lt. General John F. Sattler, chosen motivational speaker for the 71st Scientific Meeting of the American Academy of Forensic Sciences (AAFS), brought his military background into the discussion of the junk science problem facing courtrooms across the country. Sattler began the debate by pointing to the theme of the 2019 conference: "Diligence (to the Effort), Dedication (to the Handling of Details), Devotion (to the Field)." These were the words that headed the top of the program handed out to all attendees. He spoke about how these goals could not fail a person in their daily goals, and if followed in forensics, these goals could solve many problems. Sattler continued with emphasis on the words, "Truth matters."
General Sattler then went on to describe that no matter what area of life, settling for the status quo is dangerous and, in some cases, deadly. Sattler specified the military bases in Iraq, and every base had a sign posted in large letters as you enter, "Complacency kills." His point in telling this story was that becoming complacent about the types of forensic evidence that was being used in court trials had killed innocent victims. He wanted to bring that point home to the attendees, which consisted of lawyers, scientists, and forensic specialists worldwide.
Hair analysis results across the country have been rebuked, turned over since the 2015 revelation regarding the junk science coming out of the FBI's hair microscopy division. The news regarding wrongful convictions was more than alarming. According to testimony given by the FBI, their hair microscopy division specialists had given erroneous statements on the stand in court testimony, convicting 33 death row cases that were later found to be wrongfully convicted. Of these 33 cases, "Nine of these defendants have already been executed, and five died of other causes while on death row."
With this type of damning evidence, what then is the value of hair analysis at all? It is still a very relevant part of crime scene investigation. However, depending on the results, some of it is not considered science as recognized under the rules of the scientific method. Comparing hair microscopically can give some indication towards the identity of a suspect, though it cannot confirm it based on a view comparison. It can look for cells or roots that are still attached to the hair, which could lead directly to a DNA analysis that could conclusively include or exclude a defendant.
Pulling all of this together, as a crime scene investigator, it is essential to gather as much evidence as possible to solve the crime. This would include any available hair that can be analyzed. Be aware; those results cannot distinctively point out your suspect. It can be the icing on the cake. If you have other positive identifying evidence, a comparison can suggest that hair is similar to the hair that belongs to your suspect. You may even get lucky and find a way to DNA analysis through your hair samples. Every sample can be a clue. The idea is to allow the evidence to lead you to solve crime situations and not use the clues to fit a specific scenario. If you follow this, and of course the 3 D's above, your career in forensics, law enforcement, or crime scene investigation is sure to go far.