 He also served as chaplain of the New York chapter of the Knights of Columbus; spiritual director of the archdiocesan Union of the Holy Name Societes; and Grand Prior of the American chapter of the Knights of the Holy Sepulchre, an order in which he held the rank of Knight Grand Cross.He was ecclesiastical superior of the Sisters of St. Dominic, and was instrumental in the development of Mount St. Mary College in Newburgh.Dunn died from a heart attack at St. Vincent's Hospital, at age 63.