Let’s get a few ideas on the plate to start with.
First is commitment bias, where instead of thinking fresh, you double-down on your existing position. It’s bad enough when you do it, altering your decisions to align with what you’ve said and done in the past to remain consistent (we like appearing consistent and feel that it makes us seem more rational). Doubling down on a (bad) decision because you are trying to protect your image is a type of sunk cost, a throwing of good money (or time, resources, whatever) after bad. But it’s worse when it is integrated into a systemic way of thinking, baked into an organization’s culture. This bias gets amplified when the organization’s status is being questioned, like, not for nothing, a police department under pressure to solve a series of homicides. Commitment bias is one way innocent people get wrongfully convicted and, worse, when criminals are not caught and continue to commit their horrible actions.
Second, from an editorial of mine in Forensic Science International: Synergy (disclosure: I’m Editor in Chief), where I said:
Humans have a decision-making system which is biased to avoid costly false negatives while the criminal justice system is designed to be biased in the opposite way, avoiding costly false positives. But systems fail, people do not; a badly out of kilter system can lead even the most expert to bad outcomes. Perverse incentives, driven by the fetishizing of DNA, put pressure on an already-stressed forensic system. Every system needs feedback, both positive and negative, to correct itself and stay stable, forensic science is only one of those in a criminal justice system. Recognizing false positives, false negatives, and how they happen is critical to stabilizing and calibrating a criminal justice system. Oversight, review, and addressing wrongful convictions is a necessary form of feedback to forensic science and any balanced and fair criminal justice system.
I go on to explain how the human decision engine clashes with the criminal justice decision engine and ways to acclimate the two (Read the editorial; it’s free). One of the issues I discuss in the editorial is how we in forensic science* have fetishized DNA as evidence:
DNA became fetishized as the pinnacle of evidence, taking on powers and meaning beyond its storage and replicatory capacities. DNA went from a simple molecule to the maker or breaker of cases, its meaning and relationship to cases and their success changing much as if a pawn had suddenly become a queen on a chessboard [16, page 88]. The molecule had not changed but its place in the forensic pantheon of evidence surely had, altering the forensic enterprise forever. DNA The Molecule had been replaced by DNA The Unicorn, fetishized through the “common process whereby inanimate, material things get drawn into social relations between people and take on a life of their own”.
So, the criminal justice system (or should I say the criminal justice* system, in light of the use of the asterisk in this Substack) have commitment bias and a DNA fetish.
What could go wrong? Well, this:
Nearly 20 years before Ridgway was arrested, the Washington State Patrol Crime Laboratory overlooked key microscopic evidence found on the clothing of his very first victim — and of seven others who followed — according to interviews and a review of thousands of pages of documents obtained through public records requests. The tiny spheres of a unique industrial spray paint linking Ridgway to their murders could have been detected back in the 1980s, forensic scientists involved in the case recently acknowledged, possibly preventing at least some of his 49 confirmed killings.
Yes, that’s right: Trace evidence. TRACE EVIDENCE. Those bits and pieces, the flotsam and jetsam of our material and biological lives, the remnants, the vestiges of our daily activities, the exact stuff that gets ignored and devalued because of--ahem--our fetish with DNA. This is, of course, Gary Ridgway, the so-called Green River Killer. Ridgway spray-painted Kenworth semi-trucks for a living; his clothing and some of the evidence from the victims had small glossy acrylic urethane spheres on them.
As a friend and colleague once said, “DNA only tells you who; all the other evidence tells you what, where, when, why, and how.” The laboratory at the time was swamped with cases, had too few people, not enough resources. Sound familiar?
But with the volumes of evidence, the staffing constraints and the workload of other cases statewide, crime lab officials had to choose what evidence to analyze…They opted to focus on analyzing hairs and fibers, which “usually would have been the most fruitful”...But focusing analysis on hairs and fibers meant the lab “basically ignored” smaller particles and dust on clothing and other items…
Here’s the sad part: Unlike having to wait for advances in technology and instrumentation to be able to analyze the tiny bits of evidence, the ability to analyze these paint spheres was readily available in the 1980s when the homicides were being investigated (more or less). The trouble was no one at the lab had the experience or the knowledge to know what the spheres were or what to do with them. You have to recognize evidence before you can analyze it and make sense of it. You also need to have a deep understanding of manufacturing and supply chains to appreciate the evidence you get.
It took 17 years for the lab to recognize that they needed to call in someone, a trace evidence wizard named Skip Palenik (hey, Skip!). The glossy acrylic urethane spheres were air-dried droplets of a distinct commercial automotive spray paint, made by DuPont and called Imron. DuPont had patented the high-end, specialty Imron paint and were pretty sure no other manufacturer was making paint with Imron’s unique composition or pigments. The paint wasn’t publicly available in 1982 and Kenworth was the only location in the Seattle area that used that paint in the 1980s.
“Imagine in ’85, after I was out there, if [the lab] sent this stuff back to us, we’d find and identify the spheres as this unusual urethane paint,” Palenik said. “And then when they bring in a suspect and it’s Gary Ridgway — well, where does he work? He works at a place where he sprays the very same unusual paint on trucks all day.”
Had that happened, the paint spheres could have been detected back in the 1980s, linked Ridgway to his victims, and possibly prevented at least some of his 49 confirmed killings. Read that again. Trace evidence might have saved almost 50 people.
The Business of Forensics (From Project FORESIGHT)
I get it: Trace evidence is expensive (average cost per case in 2021: $4,936) and slow (average turnaround time in 2021, in days: 204) while DNA is less so ($1,488; 133). Trace evidence case submissions are falling (despite case productivity rising), due to a shift in resources because of the COVID pandemic and the opioid crisis, as well as our collective DNA fetish. The growth in trace evidence costs was almost double that from 2013-2020 but think of the money that’s been thrown at DNA($1 billion over 5 years); what would have happened if that much money was provided to other evidence types? As a colleague of mine once said, irritating the forensic biologists he was speaking with, “You all think you’re so special. You worry about one molecule; the rest of us have to worry about all the other molecules.”
Again, from my editorial:
Blaming individual scientists or managers does not correct the systemic issues facing forensic science and its use. Systems fail, people do not; a badly out of kilter system can lead even the most expert to bad outcomes. Every system needs feedback, both positive and negative, to correct itself and stay stable. Recognizing false positives, false negatives, and how they happen is critical to stabilizing and calibrating a criminal justice system.
Maybe we in the forensic and policing professions need to keep our minds open about what evidence is important, what we haven’t tried, and avoid a systematic escalation of commitment. I’m sure Ridgway’s “additional” victims would agree.