The article draws from critical psychology to discuss the rising debate on brain determinism and free will in the legal domain. As free will also corresponds to the context and culture, it can have both the public and private space of expressions. The rise of neuroscience and its influence in the legal domain offers a holistic and sociocultural meaning of responsibility. Even one becomes entitled to take free will as a ‘necessary illusion’ in order to be in the zone of ‘moral as well as legal-social life forming activities’. In the criminal justice system free will is not taken as any kind of necessary illusion but the conscious will and action of the person. This further throw light on how self-regulation directs oneself to the wilful control of illegitimate acts and the role of brain.