Legislative by-elections were held in Vanuatu on 12 December 1988 and 28 November 1989 to fill twenty-three vacant seats, including twenty-two made vacant by a political crisis.

The legislative elections of November 1987 were won by the ruling Vanua'aku Pati, which took 26 of the 46 seats in the Parliament of Vanuatu. Walter Lini, Prime Minister of Vanuatu since the country's independence in 1980, remains head of government. The Union of Moderate Parties, led by Vincent Boulekone, won the other 20 seats and remained the parliamentary opposition. Maxime Carlot replaced Vincent Boulekone as leader of the UPM and therefore as leader of the opposition shortly after.^[1][2]

In 1988, five deputies led by Barak Sopé left Vanua'aku Pati and created the Melanesian Progressive Party. TheseThe five were subsequently expelled from Parliament on 24 July 1988 by the Speakers Onneyn Tahi, at the request of the Lini government, invoking a 1983 law that automatically vacates the seats of MPs who change political party during the parliamentary term. Barak Sopé as well as Maxime Carlot then described Walter Lini as a “dictator”, and 18 of the 20 UPM deputies started boycotting Parliament. On 27 July, after being absent from Parliament for three consecutive days, the 18 deputies were also expelled by Tahi, who considered that they had resigned their seats. In September the Supreme Court confirmed the legality of the dismissal of the 23 MPs, opening the way to the holding of by-elections.^[3] The only two UPM deputies who are not expelled were Vincent Boulekone and Gaetano Bulewak, who refused the UPM's boycott strategy. They were subsequently excluded from the UMP and founded the Tan Union.^[4][5]

The by-elections for the eighteen seats made vacant by the expulsion of deputies from the Union of Moderate Parties are being held on 12 December 1988, the expulsion of the five dissident Vanua'aku Pati MPs having been suspended by court decision. The UPM and the Melanesian Progressive Party (PPM) are boycotting them. Only Vanua'aku Pati and Union tan present candidates. For nine of the seats, there is only one candidate.^[6][7] The participation rate in constituencies where there are candidates to decide is only around 40%, with opposition supporters following the boycott instructions.^[8]

The expulsion of Barak Sopé and his four fellow deputies having finally been confirmed by the courts, partial elections for these five vacant seats are being held on 28 November 1989. Here too, only the Vanua'aku Pati and the Tan Union participated, these elections being boycotted by the UPM and the PPM.

On 16 December 1988, four days after the by-elections, the President Ati George Sokomanu declared Parliament dissolved and announced that early elections would be held in February 1989. The Lini government considered this dissolution to be unconstitutional and did not take it into account. On 18 December, President Sokomanu appoints an “interim government” led by his nephew Barak Sopé. The same day, the Lini government ordered and obtained the arrest of Sokomanu, Sopé and other members of this so-called government. On 19 December, the Supreme Court of Vanuatu declares the actions of President Sokomanu unconstitutional, as the Constitution of Vanuatu does not allow the President to dissolve Parliament on his own initiative, nor to appoint a government which does not have the confidence of Parliament.^[6]

In February 1989, the courts sentenced President Sokomanu to six years in prison for inciting mutiny and seditious conspiracy. Barak Sopé and Maxime Carlot are each sentenced to five years in prison, and Willie Jimmy to three years in prison.^[8]

In September 1991, Prime Minister Lini is forced to resign following an internal rebellion within his party, and a motion of no confidence against him in Parliament. Donald Kalpokas, new leader of Vanua'aku Pati, becomes Prime Minister ahead of December elections.^[11]