Between 1962 and 1965, Justice Cornelius was associated with a Rochester law firm, now known as Woods Oviatt Gilman LLP. In 1965, he was appointed an Assistant District Attorney for the Monroe County District Attorney's Office, and served in the capacity of a prosecutor of criminal cases until 1977. In 1977, Justice Cornelius was elected a Monroe County Family Court Judge, and served on this court between 1978 and 1985. In 1985, Justice Cornelius was elected a Supreme Court Justice for the Seventh Judicial District, and in 1999 was re-elected to that court. As a Supreme Court Justice, he presided over all types of civil and criminal cases, and was frequently assigned to preside over trials in New York City.
During his judicial career, Justice Cornelius served as Supervising Judge of Family Courts for the Seventh Judicial District, a member of the Litigation Coordinating Panel for the State of New York, member of the Continuing Legal Education Board of the State of New York, and Education Liaison for the Seventh Judicial District to the New York State Judicial Institute.
On January 1, 2007, Justice Cornelius became associated, as counsel, with the law firm of McConville, Considine, Cooman & Morin, P.C., in Rochester, New York, where he assists the litigation department and conducts arbitrations. He is also a member of the Commercial Panel of the American Arbitration Association (AAA), a member of the Financial Industry Regulatory Authority Board of Arbitrators (FINRA), and conducts private arbitrations as well. Decisions, issued following arbitration hearings, have resolved disputes involving such matters as commercial and employment contracts, and apportionment of liability in medical malpractice cases.
- New York State Bar
- State of Florida
- United States District Court, Western District of New York
- Supreme Court of the United States
- University of Michigan Law School, J.D.
- Binghamton University, B.A.
- Monroe County Bar Association
- Florida Bar Association
- Brevard County Bar Association
Justice Cornelius has been involved in many activities related to continuing legal education. These have included the presentation of legal courses for the Judicial Institute, Office of Court Administration, New York State Bar Association, Erie County Bar Association, and Monroe County Bar Association. The subjects of his presentations have included evidence, civil procedure, guardianships and infant settlements. Justice Cornelius is a former Dean of the Monroe County Bar Association’s Academy of Law, and a recipient of the Bar Association's Pauley Award and President's Award. In 2006 and 2007, Justice Cornelius was a member of delegations to Novgorod, Russia, as part of the Russian American Rule of Law Consortium program, and spoke on the subjects of continuing legal education in the United States and expert witness testimony.