Wis. Admin. Code EL § 2.07 : — Elections CommissionElection Related Petitions — Challenges to nomination papers

(1) The elections commission shall review any verified complaint concerning the sufficiency of nomination papers of a candidate for state office that is filed with the elections commission under ss. 5.05 and 5.06, Stats.; and the local filing officer shall review any verified complaint concerning the sufficiency of nomination papers of a candidate for local office that is filed with the local filing officer under s. 8.07, Stats. The filing officer shall apply the standards in s. EL 2.05 to determine the sufficiency of nomination papers, including consulting extrinsic sources of evidence under s. EL 2.05(3).
(2)
(a) Any challenge to the sufficiency of a nomination paper shall be made by verified complaint, filed with the appropriate filing officer. The complainant shall file both an original and a copy of the challenge at the time of filing the complaint. Notwithstanding any other provision of this chapter, the failure of the complainant to provide the filing officer with a copy of the challenge complaint will not invalidate the challenge complaint. The filing officer shall make arrangements to have a copy of the challenge delivered to the challenged candidate within 24 hours of the filing of the challenge complaint. The filing officer may impose a fee for the cost of photocopying the challenge and for the cost of delivery of the challenge to the respondent. The form of the complaint and its filing shall comply with the requirements of ch. EL 20. Any challenge to the sufficiency of a nomination paper shall be filed within 3 calendar days after the filing deadline for the challenged nomination papers. The challenge shall be established by affidavit, or other supporting evidence, demonstrating a failure to comply with statutory or other legal requirements.
(b) The response to a challenge to nomination papers shall be filed, by the candidate challenged, within 3 calendar days of the filing of the challenge and shall be verified. After the deadline for filing a response to a challenge, but not later than the date for certifying candidates to the ballot, the elections commission or the local filing officer shall decide the challenge with or without a hearing.
(3)
(a) The burden is on the challenger to establish any insufficiency. If the challenger establishes that the information on the nomination paper is insufficient, the burden is on the challenged candidate to establish its sufficiency. The invalidity or disqualification of one or more signatures on a nomination paper shall not affect the validity of any other signatures on that paper.
(b) If a challenger establishes that an elector signed the nomination papers of a candidate more than once or signed the nomination papers of more than one candidate for the same office, the 2nd and subsequent signatures may not be counted. The burden of proving that the second and subsequent signatures are that of the same person and are invalid is on the challenger.
(c) If a challenger establishes that the date of a signature, or the address of the signer, is not valid, the signature may not be counted.
(d) Challengers are not limited to the categories set forth in pars. (a) and (b).
(4) The filing officer shall examine any evidence offered by the parties when reviewing a complaint challenging the sufficiency of the nomination papers of a candidate for state or local office. The burden of proof applicable to establishing or rebutting a challenge is clear and convincing evidence.
(5) Where it is alleged that the signer or circulator of a nomination paper does not reside in the district in which the candidate being nominated seeks office, the challenger may attempt to establish the geographical location of an address indicated on a nomination paper, by providing district maps, or by providing a statement from a postmaster or other public official.

Wis. Admin. Code Elections Commission § EL 2.07

Renumbered from G AB 2.07, correction in (1), (2) (b) made under s. 13.92(4) (b) 6, Stats., and correction in (1), (2) (a) made under s. 13.92(4) (b) 7, Stats., Register June 2016 No. 726, eff. 7/1/2016.