The government of the Isle of Man is a parliamentary representative democracy. As a Crown Dependency, it is not subordinate to the government of the United Kingdom. That government, however, is responsible for defence and external affairs and could intervene in the domestic affairs of the island under its residual responsibilities to guarantee "good government" in all Crown dependencies. The Monarch of the United Kingdom is also the head of state of the Isle of Man, and generally referred to as "The Queen, Lord of Mann". Legislation of the Isle of Man defines "the Crown in right of the Isle of Man" as separate from the "Crown in right of the United Kingdom". Her representative on the island is the Lieutenant Governor of the Isle of Man, but his role is mostly ceremonial, though he does have the power to grant Royal Assent (the withholding of which is the same as a veto).
Although the Isle of Man is not part of the United Kingdom, its people are British citizens under UK law — there is no separate Manx citizenship. The United Kingdom is responsible for all the island's external affairs, including citizenship, defence, good governance, and foreign relations. The island has no representation at either the UK or EU parliaments.
The legislative power of the government is vested in a bicameral (sometimes called tricameral) parliament called Tynwald (said to be the world's oldest continuously existing parliament), which consists of the directly-elected House of Keys and the indirectly chosen Legislative Council. After every House of Keys general election, the members of Tynwald elect from amongst themselves the Chief Minister of the Isle of Man, who serves as the head of government for five years (until the next general election). Executive power is vested in the Lieutenant Governor (as Governor-in-Council), the Chief Minister, and the Isle of Man's Council of Ministers. The judiciary is independent of the executive and the legislature.
Douglas, the largest town on the Isle of Man, is its capital and seat of government, where the Government offices and the parliament chambers (Tynwald) are located.
The Head of State is the Lord of Mann, which is a hereditary position held by the British monarch (currently Queen Elizabeth II). The Lieutenant Governor is appointed by the Queen, on the advice of the UK's Secretary of State for Justice, for a five-year term and nominally exercises executive power on behalf of the Queen. The Chief Minister is elected by Tynwald following every House of Keys general election and serves for five years until the next general election.
When acting as Lord of Mann, the Queen acts on the advice of the Secretary of State for Justice and Lord Chancellor of the United Kingdom having prime responsibility as Privy Counsellor for Manx affairs.
The executive branch under the Chief Minister is referred to as "the Government" or the "Civil Service", and consists of the Council of Ministers, nine Departments, ten Statutory Boards and three Offices. Each Department is run by a Minister who reports directly to the Council of Ministers. The Civil Service has more than 2000 employees and the total number of public sector employees including the Civil Service, teachers, nurses, police, etc. is about 9000 people. This is somewhat more than 10% of the population of the Island, and a full 23% of the working population. This does not include any military forces, as defence is the responsibility of the United Kingdom.
The Manx legislature is Tynwald, which consists of two chambers. The House of Keys has 24 members, elected for a five-year term in two-seat constituencies by the whole island. The minimum voting age is 16. The Legislative Council has eleven members: the President of Tynwald, Bishop of Sodor and Man, the Attorney General (non-voting) and eight other members elected by the House of Keys for a five-year term. (Often they are already Members of the House of Keys, but must leave the Keys if elected to the Council.) There are also joint sittings of the Tynwald Court (the two houses together).
In the 2016 Manx general election, on 22 September, the Liberal Vannin Party won three seats, tying their 2011 results; all 21 remaining seats were won by independents. 12 of the 24 MHKs were newly elected to office. Turnout slightly improved from 2011 with 56% of eligible voters turning out, ranging from 40% in Douglas East to 65% in Ayre & Michael.
Most Manx politicians stand for election as independents rather than as representatives of political parties. Though political parties do exist, their influence is not nearly as strong as in the United Kingdom. Consequently, much Manx legislation develops through consensus among the members of Tynwald, which contrasts with the much more adversarial nature of the British Parliament.
The largest political party is the Liberal Vannin Party, which promotes greater Manx independence and more accountability in Government.
A Manx Labour Party also exists, unaffiliated to the British Labour Party. Its candidates won a combined 1.4% of the overall vote in 2016.
A political pressure group Mec Vannin advocates the establishment of a sovereign republic.
The island also formerly had a Manx National Party. There are Manx members in the Celtic League, a political pressure group that advocates greater co-operation between and political autonomy for the Celtic nations.
The main political issues include the Island's relationship with the finance sector, housing prices and shortages, and the Manx language.
The UK Parliament has paramount power to legislate for the Isle of Man on all matters, but it is a long-standing convention that it does not do so on domestic ('insular') matters without Tynwald's consent.
Occasionally, the UK Parliament acts against the wishes of Tynwald – the most recent example being the Marine etc. Broadcasting (Offences) Act 1967, which banned pirate radio stations from operating in Manx waters. Legislation to accomplish this was defeated on its second reading in Tynwald, prompting Westminster to legislate directly.
The UK's secondary legislation (regulations and Statutory Instruments) cannot be extended to apply to the Isle of Man.
The Isle of Man is subject to certain European Union laws, by virtue of a being a territory for which the UK has responsibility in international law. These laws are those for areas not covered by the Protocol 3 opt-out that the UK obtained for the Isle of Man in its accession treaty – the areas excluded being free movement of persons, services and capital, and taxation and social policy harmonisation.
The Isle of Man has had several disputes with the European Court of Human Rights because it was late to change its laws concerning birching (corporal punishment) and sodomy.
The lowest courts in the Isle of Man are presided over by the High Bailiff and the Deputy High Bailiff, along with lay Justices of the Peace. The High Court of Justice consists of three civil divisions and is presided over by a Deemster. Appeals are dealt with by the Staff of Government Division with final appeal to the Judicial Committee of the Privy Council in the United Kingdom. The head of the Judiciary is the First Deemster and Clerk of the Rolls. The other High and Appeal Court Judges are the Second Deemster, Deputy Deemster and Judge of Appeal, all of whom are appointed by the Lieutenant Governor.
The Court of General Gaol Delivery is the criminal court for serious offences (effectively the equivalent of a Crown Court in England). It is theoretically not part of the High Court, but is effectively the criminal division of the court. The Second Deemster normally sits as the judge in this court. In 1992, His Honour Deemster Callow passed the last-ever sentence of death in a court in the British Islands (which was commuted to life imprisonment). Capital punishment in the Isle of Man was formally abolished by Tynwald in 1993 (although the last execution on the island took place in 1872).