Brain Electrical Oscillation Signature Profiling (BEOSP), also referred to as Brain fingerprinting developed by Dr. Farwell in 1991, is a neuro-psychological method used for studying the response of the Brain to the presence or absence of a piece of information. It is based on the detection of P300 or P300 MERMER response elicited on encountering a stimulus previously stored in the brain as a form of memory. It is a noninvasive, unbiased and efficient method of interrogation of suspects and militants. It is a variant of guilty knowledge testing. It results in the form of information present or information absent which is then used to determine if the person is guilty or not. Unlike polygraph testing it is not based on autonomous nervous system (ANS) response thus avoiding emotional manipulations and outbursts. It is solely computer based technique performed using a digital electroencephalogram that measures the presence or absence of electrical brain waves in the brain through electrodes placed in the scalp region of the forehead. It has shown 100% accuracy in various tests conducted by Dr. Farwell in 2012. Though there has been criticism on the methods of Farwell but till date there is no such countermeasure or denial of the technique. Hence it is one of the most promising techniques in the field of neuroscience and criminology. Besides, we can make it more effective and widespread by performing more independent tests and making the technique cost effective and available to all.