Forensic neuropsychology is a sub-specialty of neuropsychology. It encompasses the interface between law and neuropsychology. Forensic neuropsychologists are often called to be expert witnesses in both criminal and civil proceedings and give their opinion to the court about a specific issue.

A forensic neuropsychological expert provides important information to legal cases where the dimensions of dementia, brain damage, mental retardation, intellectual function, mental illness and/or trauma are at issue.

Neuropsychological evaluations provide a method for measuring neuropsychological functions and their interplay with behavior. They are designed to diagnose or confirm disability and impairment due to developmental disorders (such as Mental Retardation, Asperger's, Autism, Learning Disabilities, etc.), acquired disorders (such as traumatic brain injury, stroke, dementia, epilepsy, toxic exposure, etc.) and psychological disturbance (such as bipolar disorder, schizophrenia, major depression, post-traumatic stress disorder, etc.). All these can affect functions such as reasoning, planning, behaviors, attention, concentration, learning, memory, language, visuo-spatial skills and emotions. Evaluations include measures of all these intellectual functions as well as measures of psychological functioning to determine the effects of personality characteristics, mood dysfunction, trauma and stress variables on current legal issues and functioning, as well as measures of malingering or exaggerations of symptoms.

A forensic neuropsychological expert presents quantifiable, data driven information about the relationship between brain damage or illness, and the behavioral or cognitive consequences that are related to the legal proceedings.