Independence to Date
The Irish Free State Constitution
The Irish Free State came into existence on 6 December 1922. Â On that date, all existing laws in Ireland including those enacted by the UK Parliament up to that date became part of the laws of Ireland.
The Dail, Courts and various institutions that existed prior to that date during the revolutionary period were dismantled. Â In effect, there was deemed legal continuity from the United Kingdom government to the Free State government.
The Free State Constitution was the precursor of the current 1937 Constitution. It had many similar features. There was a Dail Eireann directly elected by proportional representation. There was a Seanad but different to the Seanad as found under the 1937 Constitution.
Ireland Free State was a dominion with the same degree of independence as other dominions such as Canada and South Africa.
There was a provision by which the Northern Ireland parliament could opt out of the Free State. This option was immediately taken up by the Northern Ireland government on commencement of the Free State.
The third Dail was the forum which approved the Constitution. An Act of the UK Parliament, the Irish Free State Act, established the state under UK law. The United Kingdom perspective was that the Free State existed by reason of the United Kingdom Parliament Act.
The Free State perspective was that it existed as an act of national self-determination. Â This had certain practical consequences and ultimately was a factor leading to the replacement of the Constitution in 1937.
IFS Institutions
The government comprised the Executive Council. Â The President of the Executive Council was the Prime Minister or the equivalent of the Taoiseach under the 1937 Constitution.
There was no President. The head of State was the King represented in Dublin by the Governor General.
The Free State Constitution provided for a High Court and Supreme Court. It also provided for Courts of local and limited jurisdiction. The Constitution contained certain fundamental rights similar to those which apply now under the 1937 Constitution.
Amendments to the IFS Constitution
The Free State Constitution itself could be amended by Act of the Oireachtas in the first eight years. Â However due in particular to continued political violence the Constitution itself was amended to provide that it could be amended by ordinary Act of the Oireachtas for a further eight years until 1938.
A significant amount of emergency legislation was introduced providing for military tribunals, extraordinary powers of detention, military courts with powers to impose the death sentence. In effect, many fundamental rights were abolished.
In tandem, during the late 1920s and 1930s dominion status itself evolved. The degree of independence enjoyed by dominions increased steadily.  In 1931 the (UK) Statute of Westminster provided that a dominion could enact legislation which conflicted with UK Parliament legislation.
Under the Free State Constitution there existed a right of appeal to the Privy Council, effectively the UK House of Lords. This was abolished and the Privy Council itself accepted its abolition as legal in 1935.
After the election of the Fianna Fail government in 1932, the British elements in the 1922 Constitution were dismantled. Â A reference to the oath of fidelity to the Crown and the right to appeal from the Supreme Court to the Privy Council were removed. Â The office of the Governor General was abolished and the remaining role of the monarch was minimal and could only be exercised with the consent of the Executive Council.
1937 Constitution
Although the UK courts held the Irish Free State Oireachtas after 1935 could change its own Constitution, the Irish Courts took the view that there were limitations even on the extent to which the Free State Constitution could be amended.
It was in this context that the 1937 Constitution was enacted. It was passed by a vote of the people as a whole.  It continued the existing laws in force. It provided that after short initial period amendments could only be undertaken by referendums.
The system of government as constituted under the 1937 Constitution preserved the Oireachtas. Â The Oireachtas constituted the Dail, the Seanad and the President.
A provision was made for a directly appointed President. The office of Taoiseach was created as head of government and Tanaiste as deputy.
Fundamental Rights
The fundamental rights in the 1922 Constitution were restated but were now in a format in which they could not be readily altered or changed. The Oireachtas was not permitted to make laws in breach of the Constitution.
Provision was made for the challenge to laws by judicial review with power for the High Court to hold laws which were inconsistent with the Constitution to be invalid. See generally our separate guide on the Constitution for the present legal order provided by it.
The Constitution did not specifically provide that the State was republic although it gave it most of the characteristics. It provided the name of the State as Ireland or in the Irish language Eire.The Republic of Ireland Act 1949 designated the name of the State the Republic of Ireland and the State withdrew from the Commonwealth.
Northern Ireland
In May 1921 Northern Ireland came into its existence under the Government of Ireland Act, 1920. The legislation provided for a mirror image devolved legislature and in institutions in the resent of Ireland. The Southern Ireland provisions were stillborn and the revolutionary Dail treated its parliamentary elections as an election to the thrd Dail. It was superseded by the Irish Free State which was established by the Anglo Irish Treaty made on 6th December 1921.
Northern Ireland  had its own Parliament, executive and Courts. The Northern Ireland parliament’s competence was wide but limited in respect of certain matters. The United Kingdom parliament retained power over certain significant areas.
In 1973 due to political violence, the Northern Ireland parliament was abolished and direct rule was substituted. After a number of failed attempts, the Northern Ireland assembly was created under the Belfast Agreement, 1998.
There is to be a power-sharing executive. Its powers are broadly similar to the former Northern Ireland parliament. Certain key matters are retained by the UK government including taxation, financial services, broadcasting, international relations and trade.
The Northern Ireland Assembly was suspended on a number of occasions but has operated continuously since 2007. See our section on Northern Ireland law.
Court System
The Free State and 1937 Constitution each recognise the High Court and the Supreme Court. Â The High Court has full power in all matters. Â The Supreme Court is principally a Court of appeal on points of law. A Court of Appeal was added following a Constitutional referendum in 2013.
The powers of the pre-1922 High Courts were transferred to the new High Court established, under the 1922 Constitution. The Courts were reconstituted under the 1937 Constitution.  The Courts later decided that it was necessary to specifically reconstitute the Courts as such after the 1937 Constitution and this was done belatedly in 1961.
Both Constitutions contemplated local Courts of local and limited jurisdiction. The most radical change was the replacement of the functions performed by the Justice of the Peace and Resident Magistrates by full-time District Court Judges.  They have jurisdiction in minor civil and criminal matters.
The criminal and civil powers of the pre-1922 County Courts were transferred to the Circuit Court. They also hear appeals from the District Courts.
Northern Ireland Courts
The Courts under the pre-1922 system remained broadly the same in Northern Ireland and England and Wales until 2009. Â The High Court continued with Queens Bench and Chancery Divisions. Â There is a separate Northern Ireland Court of Appeal with a further appeal on a point of law to the House of Lords, later the Supreme Court.
The County Courts continued in Northern Ireland. Jurisdiction in serious criminal cases is vested in the Crown Court, effectively part of the High Court.
In 2009 the United Kingdom Courts full re-organised. Â The House of Lords was replaced by the so-called Supreme Court of the United Kingdom although the change was largely in name only.
Government Departments and Other Bodies
The Ministers and Secretaries legislation passed in 1924 shortly after independence, created the government departments and the structure of ministerial responsibility. Pre-independent functions of various bodies either based in Ireland or branches of the UK administration were transferred to the respective departments.
The departments have been reorganised on a number of departments have increased and they have been reorganised over the years. There is a constitutional limitation on the number of Cabinet ministers which has tended to restrain creation of new departments.
Shortly after independence, the local government legislation was reformed. The rural districts councils were abolished and absorbed into the county councils.  Shortly after the poor law system was revised.
Following difficulties in councils with the elected members failing to strike budgets and the ultimate abolition of several councils, the city councils and latterly all county councils were radically reformed by the introduction of the county management system. The role of the elected members was diminished to a supervisory role while the executive functions of the council were headed up by county managers and his assistants.
The Royal Irish Constabulary was replaced by An Garda Siochana. The former separate police force in Dublin was amalgamated into An Garda Siochana in 1935.
The Department of Agriculture was given an enhanced world in view of the special provision position of agriculture. Â A significant amount of legislation was passed in the first two decades of the State providing for regulation of standards and hygiene in agricultural products and latterly for market supports.
Economic Matters
The radical Fianna Fail government of the 1930s, the worldwide depression, the so-called economic war followed by the Second World War ushered in an era of high tariffs and self-sufficiency. Domestic industries were supported A number of industrial and agricultural banks were incorporated. The ESB was formed as a State company together with substantial State-run industry in the area of peat production, Bord na Mona, sugar beet. Domestic industries were subsidised behind high tariff walls.
After the railways and transport were regulated railway companies had come to be loss-making due to road transport competition and much of the railway system was nationalised after the Second World War into CIE. The State legislation in respect of transport left CIE in a virtual monopoly position.
The 1950s saw Ireland fall behind the rest of Western Europe severely and the protectionism and isolation were perceived to have outlived its usefulness.
The policy of attracting multinational investment was commenced in the 1950s on the basis of export sales relief, zero taxation relief for exports. Through the 1960s membership of the European Union Mars was sought in conjunction with British membership.  After a number of false starts, Ireland eventually join the European Union in 1973.
European Union
The Republic of Ireland joined the European Economic Communities on the 1st January 1973 following a constitutional referendum. Â The Supreme Court later held that each subsequent significant amendment of the European Union Treaties required a referendum.
There have been subsequent referendums on the single European Act (1986), the Maastricht Treaty (1993), the Nice Treaty (2001 and 2002) and the Lisbon Treaty (2008 and 2009). See our section on European Union law which has come to be very significant.
The European Union brought radical change to the Irish legal and economic system. An enormous body of European Union legislation came into force and overrode much-existing legislation. In contrast to the policies of protecting industries, the EEC treaty was based on freedom to compete, open markets and deregulation of State authorities.
The European Economic Communities, the European Communities and later the European Union itself grew organically through the 1980s and 90s with the Singel European Act, the Maastricht Nice and Lisbon Treaties.
European Union law required the removal of subsidies and regulation in certain markets. Increasingly standards were set at European Union level to facilitate the common market. Remaining public monopolies were obliged to operate on a commercial basis of quantifiable subsidies for social reasons.
The common agricultural policy in its initial form led to highly regulated markets in agricultural products as part of an elaborate system of price supports.  This has been gradually dismantled. The common market and the basic system still exist but the level of price control is minimal.
The bulk of subsidies are paid through the Single Farm Payment and Basic Payment Scheme. State monopolies have been put on a more commercial basis such as telephone, electricity, transport monopolies.
The deregulation of financial markets for banks led to a radical nature in the change of banking. Â EU financial services legislation facilitated Ireland being used as a base for the provision of financial services.