23 December 1920

The Government of Ireland Act partitioned Ireland, creating two home rule states of Northern Ireland and Southern Ireland. It was effectively the constitution of Northern Ireland from 1921 until 1972. This extract from the act of parliament summarises its main provisions.

An Act to Provide for the Better Government of Ireland, 10 & 11 Geo. V. Ch. 67 (23 December 1920)

Establishment of Parliaments for Southern Ireland and Northern Ireland and a Council of Ireland

1 (1) On and after the appointed day there shall be established for Southern Ireland a Parliament to be called the Parliament of Southern Ireland consisting of His Majesty, the Senate of Southern Ireland, and the House of Commons of Southern Ireland, and here shall be established for Northern Ireland a Parliament to be called the Parliament of Northern Ireland consisting of His Majesty, the Senate of Northern Ireland, and the House of Commons of Northern Ireland …

2 (1) With a view to the eventual establishment of a Parliament for the whole of Ireland, and to bringing about harmonious action between the parliaments and governments of Southern Ireland and Northern Ireland, and to the promotion of mutual intercourse and uniformity in relation to matters affecting the whole of Ireland … there shall be constituted … a Council to be called the Council of Ireland.

Power to Establish a Parliament for the Whole of Ireland

3 (1) The Parliaments of Southern Ireland and Northern Ireland may, by identical Acts agreed to by an absolute majority of members of the House of Commons of each Parliament … establish, in lieu of the Council of Ireland, a Parliament for the whole of Ireland, consisting of His Majesty and two Houses …

Legislative Powers of Irish Parliaments

4 (1) … the Parliament of Southern Ireland and the Parliament of Northern Ireland shall respectively have power to make laws for the peace, order, and good government of Southern Ireland and Northern Ireland with the following limitations, namely, that they shall not have power to make laws except in respect of matters exclusively relating to the portion of Ireland within their jurisdiction … and that they shall not have power to make laws in respect of the following matters in particular, namely:

• The Crown, or the succession to the Crown, or a regency, or the property of the Crown ... or the Lord Lieutenant …

• The making of peace or war, or matters arising from a state of war …

• The navy, the army, the air force, the territorial force, or any other naval, military, or air force, or the defence of the realm, or any other naval, military, or air force matter …

• Treaties, or any relations with foreign states …

• Dignities, or titles of honour …

• Treason, treason felony, alienage, naturalization, or aliens …

• Trade with any place out of the part of Ireland within their jurisdiction ...

• Submarine cables

• Wireless telegraphy

• Aerial navigation

• Lighthouses, buoys, or beacons …

• Coinage; legal tender; negotiable instruments (including bank notes) …

• Trade marks, designs, merchandise marks, copyright, or patent rights …

Prohibition of Laws Interfering with Religious Equality … 

5 (1) In the exercise of their power to make laws under this Act neither the Parliament of Southern Ireland nor the Parliament of Northern Ireland shall make a law so as either directly or indirectly to establish or endow any religion, or prohibit or restrict the free exercise thereof, or give a preference, privilege, or advantage, or impose any disability or disadvantage, on account of religious belief or religious or ecclesiastical status, or make any religious belief or religious ceremony a condition of the validity of any marriage, or affect prejudicially the right of any child to attend a school receiving public money without attending the religious instruction at that school, or alter the constitution of any religious body … or divert from any religious denomination the fabric of cathedral churches … or take any property without compensation.

Powers of the Council of Ireland

10 (3) The Council may consider any questions which may appear in any way to bear on the welfare of both Southern Ireland and Northern Ireland, and may, by resolution, make suggestions in relation thereto as they may think proper, but suggestions so made shall have no legislative effect … 

Constitution of the Houses of Commons

14 (2) The House of Commons of Northern Ireland shall consist of fifty-two members …

14 (3) The members shall be elected … according to the principle of proportional representation, each elector having one transferable vote … 

Powers of Taxation

22 (1) The imposing, charging, levying, and collection of customs duties and of excise duties on articles manufactures and produced … and collection of income tax … and excess profits duty, corporation profits tax, and any other tax on profits shall be reserved matters, and the proceeds of those duties and taxes shall be paid into the Consolidated Fund of the United Kingdom.