Born in Dublin, County Dublin, Ireland, in 1930, McDermott studied for the priesthood first with the Dominicans, then at St. Patrick's, Carlow College, completing his studies he was ordained a priest on 5 June 1955 for the Diocese of Birmingham in Alabama, United States.
McDermott was born in Dublin, Ireland in 1930 and went on to study for the priesthood with the Dominicans and later at St. Patrick's College in Carlow. He was ordained a priest on June 5, 1955, serving the Diocese of Birmingham in Alabama.