Their judgement, in essence, identified a lacuna in the existing legislation, which would disqualify the Reverend MacManaway. While the Irish Church Act 1869 did disestablish the Church of Ireland, since there was no express provision in that Act permitting its clergymen to sit as MPs, the unfortunate MacManaway would still be subject to the strictures of the House of Commons (Clergy Disqualification) Act 1801, which debarred any person 'ordained to the office of priest or deacon' from sitting or voting in the House of Commons.

James Godfrey MacManaway was born in County Tyrone in 1898, the youngest son of the Rt. Rev. James MacManaway, Church of Ireland Bishop of Clogher. He was educated at Campbell College, Belfast, and Trinity College, Dublin.

He served in the Royal Flying Corps during the First World War, having enlisted at the age of 17. In 1925 MacManaway was ordained as a priest of the Church of Ireland by the Bishop of Armagh. He married Catherine Anne Swetenham Trench, née Lecky, in 1926. He was Rector of Christ Church, Derry from 1930 to 1947. He served as Chaplain to Forces during the Second World War. In 1945 he was awarded an MBE.

In June 1947 MacManaway was elected to the Parliament of Northern Ireland, as Unionist member for the City of Londonderry. He then set his sights on Westminster, although, as a man of the cloth, there was some doubt as to his eligibility, owing to various historical statutes debarring clergymen of both the Established Church and the Roman Catholic Church from sitting as MPs in the British House of Commons.

Modern scholars have questioned the rationale of this decision, but, nonetheless, the House of Commons resolved on 19 October 1950 that MacManaway was disqualified from sitting. The House did, however, indemnify him from the £500-a-time fines that he had incurred for voting in parliamentary divisions while ineligible. MacManaway had voted on five occasions.

In the aftermath of the MacManaway case, in 1951 another Select Committee examined the possibility of a change in the law. However, while acknowledging the anomalous and anachronistic nature of the ancient legislation, and taking soundings from various Christian denominations, the Committee recommended no specific change to the law. The law did not, however apply to churches such as the Presbyterian Church in Ireland and ministers such as Martin Smyth successfully served as MPs.

There the matter lay for almost 50 years, until David Cairns was selected to fight the safe Labour seat of Greenock and Inverclyde. Cairns was a former Roman Catholic priest, and a re-run of the MacManaway imbroglio loomed. The Labour government introduced a bill removing almost all restrictions on clergy of whatever denomination from sitting in the House of Commons. The only exception would be Church of England Bishops, because of their reserved status as members of the House of Lords. The bill came into law as the House of Commons (Removal of Clergy Disqualification) Act 2001 in time for David Cairns to take his seat in the Commons.