Idaho constitution
Article XVIII
Section 4a

Counties of the state of
Idaho as they now exist, or may hereafter be created or exist, may be consolidated
in such manner as shall be prescribed by law; provided, no county may be
consolidated with another county, except upon approval of a two-thirds (2/3)
majority vote in each county, of the qualified electors thereof voting upon the
question, and the limitations and provisions of sections 2, 3 and 4 of Article XVIII
of the Constitution of the state of Idaho shall have no application to the question of
consolidating counties.