How your nose can be a witness to crime

If you are planning a jewellery heist (can the word “heist” be used in any other context?) or some other nefarious activity that you would rather not be linked to, then you will need to do more than wear a mask and gloves to hide your identity. A new study has shown that your smell will give you away, as nose-witnesses can be just as reliable as eye-witnesses.

We already know that each person has their own odourprint and can be identified from it. However, these researchers wanted to see how human odour memory operates following stressful events. To do this, they had people watch videos of people committing violent crimes. They were also exposed to a body odour that they were told belonged to the perpetrator. They also watched neutral videos in which no crime was committed but again were exposed to the body odour of the person in the video.

Subjects were then asked to identify the criminal’s body odour from a line-up of five body odours.

These researchers wanted to see how human odour memory operates following stressful events.

The results showed that the subjects correctly identified the criminal via his body odour 70 per cent of the time. Further studies showed that people could identify the criminal in line-ups of up to eight people, although after that their accuracy waned. Nose-witnesses also did less well when a week had elapsed between the first smelling and the line-ups.

Interestingly, the subjects were far more accurate when they had seen the violent crime than when they saw the neutral video, suggesting that there is an emotional component to this olfactory memory.

It could be that soon witnesses in criminal trials will be asked, “Can you smell the man who robbed you in this courtroom?” Who nose?