Applied neuroscientific knowledge such as brain neuroimaging has widespread application in the medical diagnostic and treatment areas. Neuroscientific progress such as cognitive neuroscience has strong implications in specific medical fields such as forensic psychiatry. Significant progress in forensic psychiatry has affected the practice of law, in which an understanding of the complex relationship among mind, brain, and behavior is becoming necessary. Forensic psychiatry is concerned with the relationship between psychiatric abnormalities and legal violations and crimes. Due to the lack of available biological criteria, assessment, evaluation and therapy in forensic psychiatry have so far been restricted to psychosocial and mental criteria of offender personality. Recent advances in nuclear radiology such as brain imaging techniques (fMRI, DT-MRI, PET, SPECT) allow a closer approach to the neural correlates of personality, moral judgments and decision-making. Introduction of neurobiological criteria (based on advanced neuroimaging techniques) in the field of forensic psychiatry and establishing the rules to what extent such biological criteria will be more reliable choice in evaluating mentally ill offenders would be of fundamental value in the modern forensic psychiatry. Psychosocial and subjective criteria in forensic evaluation will be more accomplished by biopsychosocial and objective criteria. Advances in the neuroimaging techniques bring specificity to the problems underlying the application of neuroscience to criminal law.