A guilty suspect’s brainwaves can give them away if presented with an image, scene or weapon they have seen before
It sounds like a futuristic plot from the silver screen, but Dubai Police are using technology to examine brain activity to test whether a suspect remembers a crime scene.
Known as brain fingerprinting, the crime-fighting tool is one of the latest innovations, and it is being trialled in the UAE.
The National spoke to Capt Rashid Al Mansoori, head of the behaviour and personality assessment section, and Lt Abdelrahim Al Harmoudi, an expert in forensic psychology, to find out more.
Brain fingerprinting: technology and technique
First introduced by scientist Lawrence Farwell in the 1990s, brain fingerprinting technology was used in 1999 to help solve a 15-year-old murder case in the US.
The technique has also been used by police in India and Singapore, and now in the UAE.
The process involves attaching electrodes to a suspect’s head and showing them pictures, including an image of the crime scene.
A small but noticeable change in brain activity will occur if the suspect is presented with an image they have seen before.
This response is not influenced by emotions such as fear, stress or anxiety, said Capt Al Mansoori, who describes the readings as “brainwave science”.
“This is because of the way the system works, how the pictures are shown, and how a baseline for responses on all of the images shown is available,” he said.
Officers have used the technology to solve two murders in the emirate.
The device was developed in the US and has been tested by several US federal government agencies, which found it to be more than 99 per cent accurate.
One study concluded it was almost impossible to fool the test, stating that “BF [brain fingerprinting] is highly resistant to countermeasures”.
“No one has beaten a BF test with countermeasures, despite a $100,000 reward for doing so.”
‘Importance of consent’
The results are accurate, but they do not prove guilt.
“We can prove without doubt that brainwaves show memories that are related to the crime, but we don’t say someone is guilty,” Capt Al Mansoori said.
“The assessment confirms only that memories of a crime are present in the suspect’s brain.”
Before the assessment, permission must be obtained from the prosecution and the suspect must also agree.
“Nothing is done without the suspect’s consent, which is standard protocol,” Capt Al Mansoori said.
They are then briefed about the test before it starts, he said.
The procedure requires the suspect to put on a skullcap equipped with a set of electrodes designed to detect activity in the brain.
The suspect is then shown random images on a display screen for just a fraction of a second.
Some pictures are related to a specific crime and when the suspect sees an image they have seen before a particular electric signal, called the P300, is amplified in the brain.
The pictures can be murder weapons, objects from crime scenes, victims or victims’ clothes.
The brain responses are read by the electrodes and represented on a screen in red, green and blue that indicate either “information present” or “information absent”.
The results are submitted to prosecutors, but it is left to the judge to determine if the suspect is guilty.
“Having a memory of a bloodied body, for example, does not necessarily mean the person is the perpetrator. He could be a witness,” Capt Al Mansoori said.
Practical application in serious crimes
Dubai Police trialled the technology for a year before it was put to the test in active criminal cases in March.
Outcomes of all trials were shared with the manufacturing company for research and development purposes.
“The trials included nearly 40 mock crime scenarios. Following the trials, the technology was used to investigate two real murder cases,” Lt Al Harmoudi said.
In both cases, the suspects’ brain activity during the test showed they knew information about the crime.
An experimental study about the device is under way in collaboration with the Dubai Police Academy to conduct more systematic investigations into how it works and its efficacy.
“We have doctoral students from the academy who are interested in the technology,” Capt Al Mansoori said. “But we are constantly collaborating with the manufacturing company to further enhance the product.”