Decoding minds: The controversial rise of BEOS in Indian justice
Our memory can reveal whether we are guilty of a crime. Indian law enforcement officials have an unusual and controversial solution available to them. BEOS allows memories to be extracted from suspects' minds—even those memories the individuals may want to keep hidden.
In 2021, a 20-year-old Indian resident named Surjaram was accused by a teenage student of rape. The incident allegedly took place in a school classroom, where the teenager claimed she was lured and threatened with a knife. The girl informed her family about everything and made statements to the police.
Despite the seriousness of the allegations, Surjaram was released on bail. Jonathan Moens reported in the Science service about the entire story and the technical solutions behind it, revealing that Surjaram's release was determined by three tests requested by the suspect, who denied the allegations.
His truthfulness was assessed using a polygraph and a "truth serum"—administered in the form of barbiturate injections, which are believed to increase the likelihood of obtaining truthful information during interrogation.
Applications of electroencephalography
The third tool used to verify the suspect's credibility was BEOS (Brain Electrical Oscillation Signature Profiling). This is a non-invasive method of examining brain activity through electroencephalography (EEG), which is widely used in medicine.
By using electrodes placed on the head, it is possible—by detecting changes in electrical potential on the skin's surface—to study brain activity. This can aid in diagnosing, among other things, seizure disorders, memory loss, fainting, vision disorders, and other neurological problems.
The P300 wave
EEG also allows for the detection of the P300 wave. This is a distinctive, measurable brain response to information that is familiar and has been previously processed. Research on the P300 wave has been underway since the 1960s, initially serving primarily for diagnosing cognitive disorders.
This particular brain reaction can also be used to identify information in a person's memory that they do not wish to reveal. In the 1980s, research on brain fingerprints and lie detection through brain activity was conducted at Harvard University by Dr. Lawrence Farwell.
The outcome of this research is a pattern of brain response termed P300-MERMER (Memory and Encoding Related Multifaceted Electroencephalographic Response): several hundred milliseconds after recognising a stimulus, a positive P300 wave is observed, followed—about 1,200 ms later—by a negative wave. This pattern is clearly visible on a graph of brain activity.
This research captured the interest of U.S. security agencies, but at the start of the 21st century, organisations such as the FBI and CIA dismissed Dr. Farwell's method as not particularly useful. However, Pakistan took a different stance, and its authorities collaborated with the scientist.
BEOS reveals hidden memories
Building on these discoveries, a neurobiologist working at the National Institute of Mental Health and Neurosciences in Bangalore, Prof. Champadi Raman Mukundan, developed the BEOS procedure. According to its creator, it is possible to distinguish reactions to events known indirectly—such as from rumours or news—from those related to events in which the subject participated.
As a result, BEOS can function not only as a lie detector but also—by exposing the brain to an appropriately selected set of stimuli—force the person being tested to reveal memories they prefer to keep secret. The Indian justice system has employed this technique at least 700 times. The development and promotion of the BEOS method—even beyond India—is handled by the company Axxonet, founded by Prof. Mukundan.
BEOS - controversies and criticism
The problem is that BEOS is a method rife with controversy. Critics argue that the difference between memories related to events a person participated in and those related to their imagination is too small or impossible to detect.
This raises concerns about the reliability and, therefore, the overall utility of the method. Moreover, even experiments conducted by Axxonet have shown that it yields about 5% false positives, suggesting, for instance, involvement in a crime by individuals who are completely innocent.
Consequently, as early as 2010, the Indian Supreme Court prohibited the use of the BEOS method without the subject's consent and also restricted the admissibility of evidence collected in this way during trials. Despite the criticism, BEOS continues to be used in India, and its advocates present the method as an alternative to police torture and a means to make the Indian justice system "more humane."
