Lyle H. Rossiter, Jr, MD  (1937-2019) received his medical and psychiatric training at the University of Chicago and served for two years as a psychiatrist in the United States Army. He maintained both a  forensic and private clinical practice in the Chicago area.

Dr. Rossiter was board certified in both general and forensic psychiatry. For over forty years he diagnosed and treated mental disorders, with a special interest in personality pathology and its developmental origins. He was retained by numerous public offices, courts and private attorneys as a forensic psychiatrist and consulted in more than 2,700 civil and criminal cases in both state and federal jurisdictions. He also lectured to various groups on a variety of subjects ranging from psychotherapy to the prevention of suicide.