Sir Timoci Uluiburotu Tuivaga (21 October 1931 – 30 December 2015) was a Fijian judge, who was Chief Justice from 31 March 1980 to 31 July 2002, when he retired.
Together with two other judges, Michael Scott and Daniel Fatiaki (who later succeeded him as Chief Justice), Tuivaga advised the then-President, Ratu Sir Kamisese Mara, to abrogate the Constitution, as requested by the Military.
An Interim Military Government, headed by Commodore Frank Bainimarama took power, abrogated the Constitution, and promulgated the Administration of Justice Decree, which Tuivaga had drafted.
Fiji Law Society President Peter Knight condemned Tuivaga's actions, saying, "The eyes of the profession, the nation and the world are upon the judiciary.
Tuivaga was subsequently sued by members of the deposed government of Prime Minister Mahendra Chaudhry for his role in abrogating the constitution, which all judges were bound by oath to uphold.
Following his retirement as Chief Justice, the Fijian government nominated Tuivaga as Fiji's candidate for a position on the new International Criminal Court (ICC).
In what the Fijian government saw as a humiliation, he was forced to withdraw his nomination during the balloting on 9 February 2003, when the Samoan candidate Tuiloma Neroni Slade outpolled him.
In May 2005, Tuivaga spoke in favour of the government's proposed Reconciliation and Unity Commission, which would, if established, have the power to compensate victims of offenses related to the 2000 coup, and amnesty to its perpetrators, subject to presidential approval.
In the wake of the military coup which deposed the Qarase government on 5 December 2006, Interim Attorney-General Aiyaz Sayed-Khaiyum announced on 22 January 2007 that there would be an inquiry into allegations concerning the role of the judiciary in the events of 2000.
In July 2002, Tuivaga married Raijeli Vasakula, a lawyer and the eldest daughter of the former deputy prime minister and academic, Tupeni Baba, and Adi Miriama Cagilaba.