Fowler has been recognized for his work in the areas of substance abuse, criminal behavior and personality assessment. In the early 1960s, he developed a method of computer interpretation for the Minnesota Multiphasic Personality Inventory. He was appointed in 1976 by Federal District Judge Frank M. Johnson, Jr. to direct a court - ordered prison reform program that included assessing every prisoner in the Alabama prison system and recommending educational and rehabilitation programs for them. That same year, Fowler was retained by the estate of Howard R. Hughes, who had died without a will, to determine his mental status at various periods of his life.