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Dr. Jane Bock is a forensic botanist and researcher from Colorado affiliated with a number of professional organizations. She has been conducting field research for over four decades and has received numerous awards including the Ralph W. Schreiber conservation award and Hazel Barnes Prize.  I first met Dr. Bock while working in NecroSearch International. She has worked numerous murder cases across the nation and is very approachable for those seeking additional information. The field of forensic botany is fascinating. From looking at last meal evidence to disturbances from burial, plant material can provide great insight to an investigation. If you’ve never thought of including botanical evidence in one of your novels you might reconsider after reading this interview. Her new book Handbook of Forensic Botany will be released this year.

F4F:  Historically, how long have plants been used in forensic investigations?

BOCK: Forensic botany reaches far back in Western history. Plato, in his writing (Phaedo 399 BCE), describes the suicide of his teacher, Socrates, in detail. Socrates chose to commit suicide by imbibing poison hemlock (Conium maculatum). Plato’s description of Socrates’ symptoms fits exactly the pattern of poison hemlock poisoning today in the US and Europe. Forensic botany became ‘scientific’ with the inventions of the printing press (1440 AD) and the light microscope lenses (1590 AD). Using a microscopic lens, Robert Hooke described the cellular nature of cork cells, later published in his book, Micrographia. The earliest books describing plant cell types followed shortly. Forensic botany came of age in the US in 1934 when botanical evidence was used to solve the kidnapping and murder of Charles Lindbergh’s baby boy.

            Botanical evidence in courts today is accepted readily through both Frye and Dauburt examinations provided the witness shows competence in botanical knowledge. My cases have involved knowledge from three subdivisions of botany: plant anatomy, plant taxonomy, and plant ecology.

F4F:  How are plants used in last meal evidence analysis?

BOCK:  Dr. David O. Norris and I fostered the identification of food plant cells in criminal investigations and trials. Plant cells usually are enclosed in cellulose walls. These complex carbohydrate walls are virtually indestructible. They pass through the human digestive tract unchanged in their sizes and shapes. It does not matter if the plant was consumed raw, canned, frozen or cooked. Each food plant has cells that are distinctive in size and shape. We commonly examine plant cells from stomach contents. There is a rough time table for how long each stage of the human digestive process takes, and the time for stomach digestion usually is within a couple hours of consumption, then the material passes to the small intestine. This can be helpful in some homicides in estimating the time of death.

            Identifying food plant cells from the digestive tract and feces of a homicide victim may link the victim to a certain place where a meal was taken and may link a suspect’s presence to that same place. Two recent cases involved the plant foods found in the stomach contents of people whose exact diets were known (hospital and prison). When the records of the day’s meals were compared with stomach contents, we learned which meal was the victim’s last even though a suspect claimed the person had been killed after a later meal.

F4F: What are the most common types of analysis you’re asked to conduct for law enforcement?

BOCK: Plant Taxonomy: assigning the correct scientific plant name to a plant or plant fragment. Such identification can link a victim to a suspect through plant fragments found in clothes or vehicles. Such evidence also can show a place where a victim and/or suspect visited. what residences These cases are relatively common.  Plant Ecology: the relationship between plants and their environments. Here, you test ideas about where plant materials originated. In a case, a truck contained fragments from a mountain setting, but the trucker claimed the vehicle never had left the prairie. This along with other evidence led to a murder conviction.

F4F:  Some of the readers may be unaware of the use of pollen, seeds, and diatoms in forensic investigations. Can you talk a little about how they may be used to link a suspect to a crime scene?

BOCK: Most plants are made up of stems, roots, and leaves, plus reproductive parts (flower parts and seeds). These all have cellulose cell walls. However, other organisms have cell walls comprised of other substances. These plant structures can fall into the forensic botanist’s purview, and include pollen, spores, and certain microorganisms. The presence of pollen in association with a cold case homicide can suggest a season when a crime took place because the shedding of pollen is highly seasonal. Diatoms have cell walls of silica and are virtually universal in all bodies of water from mud puddles to oceans. However, species distribution and relative abundances among species have given strong evidence of the source the water in a case. Here, the water in the victim’s lungs indicated that he had been in a body of water that was distinctive from the location described by the suspect.

F4F: You’ve been involved with a number of high profile murder cases over the years. Is there any one case involving plant evidence that really stands out to you and why?

BOCK: High profile cases can be difficult if the media have publicized widely their decision about guilt. For example, in the defense for the Casey Anthony case, making trips to the courthouse involved running a gauntlet of reporters and other supporters of a guilty verdict yelling my name. Also, e-mail threats for the expert if you are involved with the ‘unpopular’ side.  The most renowned high profile murder case I’ve worked occurred over 10 years ago and has not been brought to trial. Therefore, it is an ongoing case and my evidence cannot be discussed here. This continues to weigh heavily on me because of what my partner and I know from our evidence.  In a recent cold case in Pennsylvania where the victim was an 80-year old woman, we determined the contents her last meal. It had served as the medium for the poison that killed her. We supplied a deposition and this led to a confession of the persons who killed her. Had it gone to trial it would have been very high profile.

F4F: What’s on the horizon in forensic botany? Are there new technologies that are poised to open areas of inquiry that were previously unknown?

BOCK:  A worrisome aspect of this field is that it is underutilized and under represented. The approaches described above are simple, inexpensive, and readily accepted in courts. Many more people with forensic interests must train themselves in botany.  DNA can be useful in forensic botany, but our lab does not deal with it. It is not especially useful in plant identifications because there are at least 300,000 plant species., and most of their DNA patterns are not known.  What DNA can do is link plant fragments from a single plant to a suspect to a victim, to a vehicle, to a place. This works well. DNA analysis is being streamlined and will become more so. Already some kits are showing up so that a major laboratory may not be required.

I am happy to discuss forensic botany with interested individuals, and also to point them to appropriate scientific literature.

jhbock@gmail.com or jane.bock@colorado.edu

www.janehbock.org