13-1-111. Qualifications of voter. (1) A person may not vote at elections unless the person is:
(a) registered as required by law;
(b) 18 years of age or older;
(c) a resident of the state of Montana and of the county in which the person offers to vote for at least 30 days, except as provided in 13-2-514; and
(d) a citizen of the United States.
(2) A person convicted of a felony does not have the right to vote while the person is serving a sentence in a penal institution.
(3) A person adjudicated to be of unsound mind does not have the right to vote unless the person has been restored to capacity as provided by law.