In his speech titled "Poverty and Inequality", Jacobi Kohu-Morris said the gap between the wealthy and the poor was increasing, and he offered several solutions to addressing the problem, including raising the minimum wage, subsidising housing, and free meals for pupils in decile 1-4 schools.
Competition co-adjudicator Jill Walker said the speech left her hoping she would "live long enough to see him in Parliament".
Jacobi also won the competition last year, and he is the only pupil to have won it in two consecutive years.
He was one of 13 secondary school pupils from across Otago in the competition at the King's and Queen's Performing Arts Centre in Dunedin on Thursday.
Fiona Cannon (Columba College) was second with "Life Advice from a Cereal Box", and third was Jino Kunnethedam (St Kevin's College) with "Bullying".