Traces The Memoir of a Leading Forensic Scientist and Criminal Investigator

This book was originally announced with the subtitle Every Body Leaves a Mark. Next to a clever play on words, it also nicely captures the subject. Patricia Wiltshire is a professor in forensic ecology, botany, and palynology. That last discipline is the study of pollen and spores and is widely used in archaeology, for example for radiocarbon dating. Wiltshire used to be an environmental archaeologist before stumbling into a new career in her fifties when a phone call heralded an unexpected career change. Traces tells that story and is a fascinating first-hand account of her pioneering contributions to forensic science.

Pollen and spores – shed by flowering plants, trees, ferns, fungi, etc. – are ubiquitous, but the composition of a pollen and spore assemblage in any one place is also unique. They attach themselves to shoes, clothing, and hair, and can be transferred to vehicle parts such as footwells and rubber pedal covers. Being invisibly small and strongly attracted to these materials by electrostatic interactions, they leave traces that are almost impossible to erase. With the right techniques, and not infrequently the use of dangerous chemicals, they can be isolated and studied under the microscope. And it turns out they have a remarkable power to connect people to certain places – like an invisible fingerprint that attaches itself to anyone who ventures outside, including both victims and perpetrators of crimes.

Back in 1994, when Wiltshire was first approached by a police force to help solve a gang murder, the use of plant remains in forensics was a novel concept. By taking the reader through this and other notable cases, she highlights how she developed her methods through much trial and error, often relying on, or modifying, knowledge and skills built up in a career as an archaeologist. In the process, she has pioneered a new discipline in forensics (see e.g. textbooks such as Forensic Botany or Forensic Plant Science), and has helped to convict killers, find missing persons, or corroborate stories of rape victims.

For botanists, there is much of interest in this book. Obviously, not all plants grow everywhere, many being sensitive to e.g. soil acidity and moisture, but I was surprised to learn how pollen and spore assemblages can vary dramatically over even very short distances of just metres. Palaeobotanists can confirm how hardy spores can be, and Wiltshire has found hay meadow pollen from horse dung perfectly preserved in domestic coal shafts of old houses – traces harkening back to pre-war or even Victorian times when horses were still used to deliver coal in cities. Judging by Wiltshire’s work, a lot of what palynologists thought they knew about pollen dispersal may need ground-truthing anew.

Now, forensic botany might not have the same yuck factor as the closely related discipline of forensic entomology. This is the study of all the insects that feast on a corpse – the squirming maggots and swarms of flies and beetles – that can reveal e.g. time since death, and which is another line of forensic evidence when solving crimes (see also Maggots, Murder and Men, or textbooks such as Forensic Entomology and The Science of Forensic Entomology). But this does not mean the reader does not get treated to some memorable and macabre passages. What to make of her description of removing the whole face of a corpse and, as if it were a glove puppet, handling it to wash plant material from the scalp, after which it is neatly fitted back over the skull. Yep, I also never knew that that was possible.

However, Wiltshire’s writing is not intended to shock. She may have a detached attitude towards death and see the corpses she handles as repositories of evidence, but she is conscious that these were once living people, loved by their nearest and dearest. Respect and dignity are the hallmarks of any professional in this trade, even when some situations they find themselves in can be unusual, comical even.

Throughout the book, Wiltshire also reflects on her own life, her youth growing up in Wales, a horrible childhood accident that afflicted her for years, the separation of her parents, her wandering career, a divorce, and the heart-rending loss of both a dear grandmother and her daughter. She opens one of her chapters with a quote that circulated on the internet: “Behind every strong and independent woman lies a broken little girl [...]”. Whether her past experiences predestined her for this unusual career choice, or whether her career served to harden her when dealing with difficult situations in life (probably a bit of both), she is one tough cookie.

I found Wiltshire’s searing honesty to be one of the most enjoyable aspects of the book. It came as no surprise to read that she has lost her faith and no longer believes in an afterlife – to her, the body is but biological materials that are decomposed and recycled after death. But it is eye-opening when she describes the grind of her work at the microscope as its own form of exquisite torture, the opposition in court as brutal bastards, or haughty pathologists as gods in their own mortuaries. Wiltshire does emphatically not sugar-coat things, which is a quality I much admire in people.

There have been several books in recent years written by pathologists, forensic anthropologists, and morticians. So, readers who enjoyed books such as Smoke Gets in Your Eyes: And Other Lessons from the Crematory, Stiff: The Curious Lives of Human Cadavers, All That Remains: A Life in Death, or Unnatural Causes: The Life and Many Deaths of Britain’s Top Forensic Pathologist are warmly recommended to pick up this book. Traces is a fascinating memoir that contributes to this mini-genre by highlighting the unexpected power of forensic botany and palynology. To have a pioneering researcher of this discipline write about it in her own words provides a deeply informed and unique perspective, resulting in a book that I simply could not get enough of.