Lay began his political career as a member of the Fretilin party. In 2001, he was elected as a Fretilin candidate to the Constituent Assembly of East Timor, from which the National Parliament emerged in 2002.[1][2][3] During that legislative term, he was President of the Economics and Finance Commission.[4]
By 2012, Lay had switched his allegiance to the CNRT; he served as President of the CNRT's political campaigns committee for that year's parliamentary election.[5]
On 8 August 2012, Lay was sworn in as the Minister of Tourism in the V Constitutional Government led by Prime Minister Xanana Gusmão.[6][7] When that Constitutional Government was replaced on 16 February 2015 by the VI Constitutional Government led by new Prime Minister Rui Maria de Araújo, Lay continued as a minister, under the new designation Minister of Tourism, Arts and Culture.[8][9]
In 2017, Lay defeated the incumbent Secretary General of the CNRT, Dionísio Babo Soares, in an election for that post at the party congress.[10]
In that year's parliamentary election, Lay returned to the National Parliament at #5 on the CNRT list, but he resigned on 6 September 2017, the second day of the session.[11][12] With the CNRT going into opposition after the election, Lay also lost his ministerial post upon formation of the VI Constitutional Government on 15 September 2017. One of his replacements, Manuel Vong, was sworn in as Minister of Tourism; the other, Fernando Hanjam, became Minister of Education and Culture.[13][14]
In 2018, the National Parliament was dissolved early. In the elections that followed, Lay was again elected to the parliament, this time in 4th place on the list of the Alliance for Change and Progress (AMP), of which the CNRT was part.[15] During the formation of the VIII Constitutional Government, Lay was nominated for appointment as Minister for Trade, Industry, Environment and Tourism. However, PresidentFrancisco Guterres rejected that nomination because Lay had allegedly been involved in a corruption scandal.[16][17]
In the 2023 parliamentary election, Lay was the 2nd placed candidate on the CNRT list, and was elected once again to the National Parliament.[18] However, on 1 July 2023 he was sworn in as Deputy Prime Minister, Coordinating Minister of Economic Affairs, and Minister of Tourism and Environment in the IX Constitutional Government,[19][20][21] and he therefore gave up his parliamentary seat.[18]
^Sousa, Nelson de (1 July 2023). "PR Horta sei akompaña serbisu IX Governu" [President Horta will accompany the work of the IX Government] (in Tetum). Tatoli. Retrieved 1 July 2023.