Idaho Const. art. X, § 3

The legislature may submit the question of the location of the seat of government to the qualified voters of the state at the general election, then next ensuing, and a majority of all the votes upon said question cast at said election shall be necessary to determine the location thereof. Said legislature shall also provide that in case there shall be no choice of location at said election, the question of choice between the two places for which the highest number of votes shall have been cast shall be submitted in like manner to the qualified electors of the state at the next general election.