뇌영상 증거의 과학적 증거로서의 기능과 한계

A number of neurosience techniques have been developed, including electroencephalophy(EEG) and positron emission tomography(PET). In recent years development efforts over the past decade have increasingly focused on fMRI. Developments in neuroimaging has facilitated new research investigations into normal human brain functioning and have provided important new sights into the mechanisms of many neurological and psychiatric disorders. Brain images are becoming more common in courts in America. Some lawyers and neuroscientists are critical of introducing a brain images as legal evidence in criminal courts. Therefor, before admitting to introduce functional brain images in criminal trials, court must answer these central questions: How probative for criminal responsibility is the brain images? and whether the brain images confuse or mislead, how dangerous is the brain image? Does its danger substantially outweigh its probative value?We should focus on the extent to which brain images could be used to reduce responsibility, not to establish it. Brain images are sometimes offered to show that a particular defendant is abnormal in some way that is claimed to remove or reduce criminal responsibility. But even if in many cases the defendants has a functional abnormality that is correlated with violent crime, correlation does not prove causation. To be relevant to criminal responsibility, it is not enough for the brain image to disclose an abnormality that caused the criminal behavior. Any data regarding brain structure or function is unlikely sufficiently contemporaneous to the time of the crime to be meaningful. Because of this scientific uncertainties, the use of data from brain images in the courts has to be admittable in restrictive conditions. In recent brain scan might be admissible in some situations, such as capital sentencing. We carefully consider the question, whether brain images bring more harm than good to criminal trials. Some lawyers and neuroscientists answer that only time and carefully analysis will tell. We need to determine the error rates of various methods in neuroscience and to prepare the basic guidelines of using brain images as legal evidence and establish appropriate rules governing the burden of proof.