While it’s a standard procedure in most courts, the eyewitness lineup is only 45 to 60 percent accurate, Technology.org reports.
Violent crime leaves a victim traumatized, making it difficult to remember what the assailant looked like, and that often leads to the wrong person being convicted.
In a recent study published in the journal PLOS ONE, researchers hoped to find out if our sense of smell might help us identify violent offenders more accurately, Technology.org reports.
For most people, different smells can stir up instant memories; something that other human senses aren’t as good at.
The key to this is in the olfactory bulb, a neural structure located in the forebrain that’s responsible for detecting smell, and as such, it’s part of our limbic system, an area intrinsically associated with memory and emotion. It’s due to this that some people are inclined to call it the “emotional brain.”
Our sense of smell may be the future of forensics, the study shows and Vocativ reports. Instead of the familiar criminal lineup, victims might point to offending odors, instead of fear-inspiring faces.
“Our results suggest that humans are capable of identifying a culprit by way of odor,” the researchers wrote. “When the perpetrator and the victim are close to one another, as in crimes of sexual and physical assault, and especially under visually obscure conditions, an olfactory cue may be the prevailing detail.”
Every person has a unique body odor, likely due to a mixture of hormones, genetics, and parasites, and police dogs are trained to identify these “odor-prints.” This study is the first to examine how well humans can rely on their senses of smell to identify violent criminals.
To begin with, the researchers took body odor samples from 20 healthy male volunteers, while for the next two hours and 30 minutes they worked on an assignment that wasn’t stressful, Technology.org reports. The men were instructed to refrain from doing anything that might change their baseline body odor before and while the samples were being taken.
Then the researchers randomly assigned 40 men and 40 women from the University of Aveiro, in Portugal to one of two conditions: “nosewitness” and neutral.
In the nosewitness condition, the students watched a short video depicting a violent crime, while they were primed with an odor sample. They were given “written instructions aimed to get the participant in the mindset of a witness to make the experimental model of the nosewitness situation more realistic.”
While students were in the neutral condition, they were presented with the same body odor, but in this case, they watched a video that was neutral and were given neutral instructions.
When the scientists analyzed the data, they concluded that students who were assigned to the nosewitness condition were able to identify the perpetrator 75 percent of the time.
Nevertheless, the researchers cautiously state that the students were merely instructed to associate a particular odor with a violent video in the laboratory, Vocativ reports. As to whether victims would be able to recall the brief scent of an attacker in a police lineup is an entirely different thing. Future studies will be underway to determine if nosewitness testimony can be reliable in more realistic situations.
