Irish lawthere are two legal systems in Ireland, both of which are common law systems. From the Irish Act of Union in 1800 until 1921, Ireland was ruled as part of the UK, although it had a separate court structure from which appeals could be brought to the House of Lords. With the partition of the island, two parliaments were set up, that of Northern Ireland, which comprised the six northeastern counties, being located at Stormont on the outskirts of Belfast, and that of the Irish Free State meeting in Dublin. New court systems were also created for the two parts of the island with (as is still the case) a final appeal from Northern Ireland to the House of Lords, and, in the case of the Irish Free State, an appeal to the Privy Council, although this was abolished in 1933. The Parliament of Northern Ireland had power to make laws for the ‘peace, order and good government of the province’ but could not legislate on certain matters, such as the armed forces, foreign affairs, weights and measures, and copyright, which were regarded as of national significance and reserved for Westminster. The Stormont Parliament was abolished in 1972, and from that time until 1999 Northern Ireland was subject to direct rule from Westminster. Since 1999 a Northern Ireland Assembly set up under the GOOD FRIDAY AGREEMENT has had powers devolved to it, albeit they have been suspended from time to time as a result of problems with the peace process.
The Irish Free State, which came into existence in 1922, had a status akin to that of dominions such as Australia and Canada, with a written constitution. This constitution was replaced in 1937 with the present one, which proclaimed the complete independence of Ireland (or, in the Irish language, Eire), which by the Republic of Ireland Act 1948 formally declared itself to be a republic. On independence, existing law continued to apply in the Irish Free State, and the 1937 Constitution also provided that existing law should continue in force insofar as it was not inconsistent with the Constitution. As a result it is not uncommon to find that legislation passed by the Westminster Parliament prior to independence applies in Ireland and that rules of law laid down by UK courts prior to independence are applied. Ireland is different from the UK in that its laws can be struck down by the Supreme Court if found to conflict with the Constitution in a similar way to other countries with formal constitutions such as the USA.