Forensics for Writers: Part I
I don’t know that we have any mystery writers who read the blog, but Sarah Hoyt writes ’em, and I probably will one of these days… and in the meantime, I’m most of the way through a degree in it. Well, ok, not mystery. I’m studying to become a Forensic Scientist and Investigator. It occurred to me that many of the writers who come here use mystery as sub-plots, and sometimes the main plotline. So… why not? After all, as we were joking in class the other day about what kind of castoff a cast-iron skillet would make, I can search topics with impunity that my professor complained would get her in trouble. I’m a writer!
I don’t know how long this series will be, I will let the commentators determine that to an extent. If you have questions, ask in comments and I’ll add on. I could, literally, write a book about this. I’ve certainly read enough of them. I’m not planning on doing that here. I thought I’d hit the highlights of what forensic science is capable of now, and what it may be in the not-to-distant future.
So what is forensics? How about criminalistics? I am fairly sure that our readers are well aware that it’s not CSI, and as shown on television is a far cry from reality. Forensics is, broadly, the use of science within the parameters of criminal and civil laws in the criminal justice system. Forensic science can be and is applied outside that system as investigative measures but strictly speaking forensics is science and the law. Within the field of forensics there are specialties: criminalistics, digital forensics, engineering, odontology, pathology, biology, physical anthropology, psychology, questioned documents, toxicology… a cross section of both physical and behavioural sciences. Criminalistics is what could also be referred to as the scope of a crime laboratory – much more the physical side of evidence than the esoteric workings of the human mind.
I think every textbook I have had on forensics points out, quite properly, that the science has its roots in fiction. A Conan Doyle’s Sherlock Holmes used many of the principles that would be refined by his readers into the nascent field of pursuing lawbreakers with science. Startling, to realize that storytelling would lead to, well, this 1887 excerpt from A Study in Scarlet speaks volumes:
“I’ve found it. I’ve found it,” he shouted to my companion, running towards us with a test tube in his hand. “I have found a reagent which is precipitated by hemoglobin and by nothing else… Why, man, it is the most practical medico-legal discovery for years. Don’t you see that it gives us an infallible test for blood stains?”
I could happily talk about the history of the field for some time – I have a paper written by a brilliant man who applied forensic principles to the killing fields in Serbia in the early 1900’s, one of the precipitating factors in the first World War – but the modern relevance is more fitting for this post, and if any of you are interested in historical methods we’ll separate that into a different part. It is pertinent to know, for instance, that you cannot have DNA used in a trial prior to 1987, as that was the first time it was accepted in court.
Which is another thing. What can be accepted in court, and who makes that decision? In 1923, a case regarding the polygraph came before the court, and the court rejected it with a particularly interesting turn of phrase: “Somewhere in this twilight zone the evidential force of the principle must be recognized.” Frye v. The United States established that science in the courtroom must be an established, valid method that was accepted by the scientific community. In other words, the scientific method, of experimental results that can be replicated, must have been applied to the results brought into the courtroom. The second major case, which to me seems somehow at right angles to the Frye decision, was Daubert v. Merrill Dow Pharmaceuticals, Inc. which ruled in 1993 that the ‘general acceptance’ standard of Frye was not absolute. Scientific evidence was now permitted on the sufferance of the trial judge. Judges, initially by law at the Federal level but in practice at the State level as well, were now to assume the ultimate responsibility in being a gatekeeper for the evidence presented before them whether scientific or simply that of an ‘expert’. Finally, the last significant case we will want to pay attention to is the 2009 Melendez-Diaz case, which requires that the forensic analyst appear in court, as the accused has the right to face their accuser. The repercussions of that decision are far-reaching and still being explored.
I’ve come this far, and you haven’t even seen a bit of blood spatter, I know. For most of us writing mysteries, none of this makes much difference. Which leads me down another rabbit trail (last one, I promise!) of “what sort of mystery is it?” There are all kinds of mysteries, from Police procedurals – where all the nitty-gritty of the law matters, very much – to cozies, where the protagonist might not know any of this, even though the author does. The first rule of a crime scene – touch nothing, record everything – means nothing to the cozy protagonist, and in fact their interference and ignorance may be an important part of the plot and conflict. In a detective story, removing (or inserting) something from the scene may be a more willful action. But in a police procedural where the protagonist has a clue, they will proceed with great caution when they first come on the scene. Which, by the way, is almost never as the first responder. Their first action most likely will be to take the statement of the first officer on scene. From there, they will continue, slowly, taking notes and photographing before touching anything. It’s not a fast process, something an author needs to keep in mind. Even processing a simple robbery can take hours.
Something else the TV shows get all wrong. A lab boffin (which is what I’m training to be) is not the field investigator, and they have very different skills and perspectives. It has been amusing to sit in classes with police officers who are training for the field end, and flinching when they talk about the science and miss the mark. On the other hand, I’m just as happy to not be the person who will be standing ankle deep in soot and debris and water at temperatures just above freezing carefully shoveling it out during an arson investigation. When you’re writing, keep this in mind. The investigators send the evidence to the lab, the lab analyzes it and returns results. The lab people don’t go out in the field. The lab boffins might not even be law enforcement, there are a lot of private labs these days.
And with that, our toes at the fringes of the place where all the action is, the crime scene, I will leave you until next week. Feel free to ask questions in comments, and I’ll start shaping what I want to say with what you want to know about physical evidence.