APA submitted an amicus brief arguing that the Superior Court erred insofar as it held that only physicians might qualify as experts concerning medical causation. The brief argued that psychologists are qualified to give expert testimony concerning the causes of psychological conditions since: (1) under Georgia law, psychologists are qualified and competent to identify the causes of mental and nervous disorders; (2) the court has acknowledged that psychologists are qualified to testify as expert witnesses concerning the causes of psychological disorders; and (3) by statute, Georgia recognizes psychologists' competence to diagnose and treat mental and nervous disorders and therefore necessarily recognizes psychologists' expertise in identifying the causes of such disorders. Additionally, APA's brief noted that, consistent with Georgia law, the overwhelming majority of jurisdictions to rule on this issue have held that psychologists are qualified experts on the causes of psychological disorders because: (1) training and experience render them able to provide expert testimony concerning causation of psychological conditions; (2) psychological training and practice are rigorous, scientific, and relevant to the issues at bar; and (3) neuropsychology is a respected and established scientific and professional discipline expert in identifying the existence, causes, and consequences of organic brain damage. Finally, the brief stated that neuropsychology can assess organic damage caused by neurotoxicants and can often diagnose which agent has caused the organic damage.