Chapter IV: Section 2: Representatives shall be apportioned among the several

states according to their respective numbers, counting the whole
number of persons in each state, excluding Indians not taxed. But
when the right to vote at any election for the choice of electors
for president and vice-president of the United States,
representatives in congress, the executive and judicial officers of
a state, or the members of the legislature thereof, is denied to any
of the male inhabitants of such state, being twenty-one years of
age, and citizens of the United States, or in any way abridged,
except for participation in rebellion or other crime, the basis of
representation therein shall be reduced in the proportion, which the
number of such male citizens shall bear to the whole number of male
citizens twenty-one years of age in such state.--(Ratified July 28,
1868.)

Article XV. Section I. The right of citizens of the United States to
vote shall not be denied or abridged by the United States or by any
state on account of race, color, or previous condition of servitude.