Forensic psychiatry is a sub speciality of psychiatry. It involves the legal aspects of psychiatry. Some practitioners of forensic psychiatry have taken extra training in that specific area. In the United States one year fellowships are offered in this field to psychiatrist who have completed their general psychiatry training. In Britain one is required to complete a three-year subspeciality training in forensic psychiatry, after completing ones general psychiatry training, before one can be registered as a forensic psychiatrist. In some countries general psychiatrists can practice forensic psychiatry as well. However, some countries require a specific certification from the government to do this type of work (e.g. Japan)