McLaughlin was ordained a priest in St John Lateran Basilica, Rome, on December 21, 1935. He continued further studies and remained in Rome for another six months before returning to Buffalo. On August 14, 1936 he was named as assistant at St. Joseph New Cathedral. He remained there until June 1942 when he was appointed secretary of the diocesan Tribunal. In 1946 he was appointed assistant chancellor and soon after became vice chancellor of the diocese. He became chancellor of the diocese on December 16, 1953. In November 1950 he was chosen to establish the new parish of Coronation of the Blessed Virgin Mary on Buffalo's West Side. He continued his duties at the Chancery during his time as pastor and in June 1961 was transferred from Coronation to become pastor of Blessed Sacrament Parish, Kenmore, New York. He remained at Blessed Sacrament until 1972 when he was named pastor of St. John the Baptist Parish in Kenmore. McLaughlin received several honors from the Vatican. On April 6, 1950, Pope Pius XII made him a Private Chamberlain with the title of Very Reverend Monsignor. Three years later he was raised to the rank of Domestic Prelate with the title of Right Reverend Monsignor. On December 4, 1967, Pope Paul made him a Prothonotary Apostolic. In addition to his work as chancellor, Bishop McLaughlin has been a member of the board of diocesan Consultors and a vicar general.
McLaughlin was appointed as Auxiliary Bishop of Buffalo on December 28, 1968, and received his episcopal consecration on January 6, 1969, from Pope Paul VI. This was the first time a diocesan priest from Buffalo was appointed a bishop by a pope. He was simultaneously named the Titular Bishop of Mottola. He also served as an advocate of the diocesan Tribunal, professor of Labor Ethics at the Diocesan Labor Management College, and founder of several parish Labor schools. In addition, he served as chaplain of the Catholic Guild for the Blind, and was a secretary of the Diocesan Synod. On September 14, 1968, he was made a Knight of the Holy Sepulchre at St. Patrick's Cathedral in New York City by Archbishop Terence Cooke.
Last years and death
Pope John Paul II accepted McLaughlin's letter of retirement on January 15, 1988, according to church law, which requires bishops to submit their letters of retirement on their 75th birthday. When his retirement was accepted, he became Auxiliary Bishop Emeritus of Buffalo. McLaughlin died on January 5, 2015 in Tonawanda, New York, at the age of 102.
