As advancement of technology accompanied with growing individual freedom, decreasing influence of family, religion, and society encourage intensity, rate and complexity of crimes. In our times there is growing need to evolve new advanced methods and techniques of eliciting truth from the criminal and eye witness involved in any crime. To this category of hypnosys and lie detectors, narco analysis is latest innovation and advanced technique presently employed by investing agencies all over the world, including our own country. This researcher proposes to study the scope and limitations of the latest psycho-analytical test such as narco-analysis, a new innovation in investigating techniques.