He was first elected to Parliament at the 2006 general election, as MP for Nukufetau.[3] He was then appointed Minister of Finance, Economic Planning and Industries in Prime Minister Apisai Ielemia's Cabinet.[4]
He retained his seat in Parliament in the 2010 general election,[5][6] but was not selected for Cabinet by new Prime Minister Maatia Toafa.[7] Three months later, in December, he supported Willy Telavi's successful attempt to oust the Toafa government in a motion of no confidence. Telavi became Prime Minister, and appointed Metia to his Cabinet, as Minister of Finance.[8][9]
The following month, in January 2011, a number of his constituents demanded his resignation, reportedly displeased with the fact that he had joined the Telavi government.[10] A peaceful protest march to demand that he step down took place in Funafuti, resulting in the Telavi government declaring a state of emergency and temporarily prohibiting any gathering of ten or more people.[11][12] Members of the powerful council of elders or Falekaupule from his island sought to persuade him to defect to the Opposition and help bring it to power.[1] When this directive was not followed the Falekaupule ordered Metia to resign as a member of parliament. When the Falekaupule attempted to enforce these directives through legal action, in Nukufetau v Metia, the High Court of Tuvalu determined that the directives of the Falekaupule should be rejected as the Constitution of Tuvalu was structured around the concept of a parliamentary democracy and that "[o]ne of the most fundamental aspects of parliamentary democracy is that, whilst a person is elected to represent the people of the district from which he is elected, he is not bound to act in accordance with the directives of the electorate either individually or as a body".[13]
In September 2012 he was taken ill, and spent the following months in New Zealand. He flew back to Tuvalu to vote in Parliament to approve the budget on 13 December, was admitted to the small country's Intensive Care Unit, then was flown to Fiji on 20 December where he was immediately admitted to the Suva Private Hospital.[14] He died in hospital the following day.
The by-election caused by his death would decide the future of the Telavi government, reduced by his death to a parity of seven seats apiece with the Opposition in Parliament. The government had previously survived a by-election in August 2011 caused by the death of Minister for Works Isaia Italeli.[15] The calling of a by-election for Nukufetau was delayed until the High Court of Tuvalu ordered the Prime Minister to issue a notice of elections five days after the judgment, which was delivered on 29 May 2013.[16] The election was eventually held on 28 June; Opposition candidate Elisala Pita won with more than two-thirds of the vote.[17]