It’s never easy, and certainly not common, to exhume a body. In the case of Robert Curley, however, it was imperative to finding out the truth surrounding his death. The trace evidence provided in a single strand of hair told the whole story.
Trace evidence is evidence so small that it is hard to see without magnification or enhancements such as alternative light spectrums or chemical treatment. A pioneer in this was Dr. Edmond Locard, who applied scientific methods to the interpretation of trace evidence. Locard’s exchange principle states that “every contact leaves a trace.” Meaning that a criminal will always (unknowingly) bring something on to the crime scene, and leave the crime scene with something. A common item used in trace evidence is hair. Not only is it a valuable factor in the exchange principle, but a single strand of hair contains an incredible amount of information. We pull head hair on every homicide, especially in cases where long-term drug exposure is in question, or when needed for identification purposes. Some basic questions we must ask: Does the hair belong to the perpetrator or the victim? Was the hair cut or pulled? Is the sample good enough for DNA studies? Information contained in hair was so important in this case, that it led to the decision to exhume the corpse. Despite atrophy of the body after years of being buried, we were able to retrieve a hair sample to perform hair segmentation analysis. Hair grows at a standard rate in humans, about 1.25cm a month. Certain drugs and heavy metal will cause lines in a hair follicle at the point of ingestion. It was clear in the case of Mr. Curley that he had ingested thallium salts, which a strand of his hair recorded, line by line. Given the constant rate of hair growth, we could go back from the closest marking on the hair to the scalp and do a retrogression analysis to observe the number and times of the exposure to the poison. A strand of hair provided a virtual road map to the victim’s suffering and ultimately his murder. In this way, the body spoke to me from the grave.
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More than once I have explained that my senses are heightened when I approach a crime scene. This is also true when I open a folder and review a case for the final declaration of death. I concentrate on data and the relationship between one fact and another. In short, I am looking for patterns, which give me the “why” of how things happened.
In this episode, blood patterns played an integral role in understanding what happened in Sam’s apartment. I had to examine the nature of each blood spatter pattern on two levels: macroscopically and microscopically. This is a fancy way of saying that I studied the overall scene and then studied the nature of each blood pattern to determine what they revealed about the movement of the players in the room. This process told me that the assault started at the door. Sam had opened the door and was immediately attacked frontally. Finally, the attack move deeper into the room, with the last stab wound most likely in his final moments of struggle. Wound patterns on the body that were examined in the autopsy are also very important. As my forensic pathologist and I studied the body we were able to determine the approximate length of the knife and also that it was a single-edged blade. We were also able to compare the lack of defensive wounds on Sam’s body and concurred that this was consistent with the blood pattern analysis. So you can see that once all data is collected, investigators move from the “how” to the “why,” looking at the macroscopic picture of the whole scene, not just its individual parts. I noticed on social media during the show that there was a good deal of conversation about the subsequent sentencing of all those involved in the death of Samuel Gore. His ex-wife was a suspect, but it was determined that there was not enough evidence to convict her as a participant in the murder. We must understand the high threshold that is required in criminal court: beyond a reasonable doubt. In civil cases where only monetary damages are involved there is a lesser requirement for conviction, which is the preponderance of the evidence, meaning the weight of the evidence. In other words, it’s like a scale. One of the most famous cases in criminal history was the O.J. Simpson trial, in which he was acquitted in criminal court because of faulty forensic processing, which left a reasonable doubt. He was later convicted in civil court due to the preponderance of the evidence. I believe in this strict standard in criminal court because of the disastrous consequences of being convicted for a crime you never did, even to death. Thanks so much for watching. You've made this show a success and I couldn’t be more grateful. |