(1) Upon receiving notification of the filing of the petitions, the board of state canvassers shall canvass the petitions to ascertain if the petitions have been signed by the requisite number of qualified and registered electors. The qualified voter file shall be used to determine the validity of petition signatures by verifying the registration of signers and the genuineness of signatures on petitions when the qualified voter file contains digitized signatures. If the qualified voter file indicates that, on the date the elector signed the petition, the elector was not registered to vote, there is a rebuttable presumption that the signature is invalid. If the qualified voter file indicates that, on the date the elector signed the petition, the elector was not registered to vote in the city or township designated on the petition, there is a rebuttable presumption that the signature is invalid. If the board is unable to verify the genuineness of a signature on a petition using the digitized signature contained in the qualified voter file, the board may cause any doubtful signatures to be checked against the registration records by the clerk of any political subdivision in which the petitions were circulated, to determine the authenticity of the signatures or to verify the registrations. Upon request, the clerk of any political subdivision shall cooperate fully with the board in determining the validity of doubtful signatures by rechecking the signature against registration records in an expeditious and proper manner.

    (2) The board of state canvassers may hold hearings upon any complaints filed or for any purpose considered necessary by the board to conduct investigations of the petitions. To conduct a hearing, the board may issue subpoenas and administer oaths. The board may also adjourn from time to time awaiting receipt of returns from investigations that are being made or for other necessary purposes, but shall complete the canvass at least 2 months before the election at which the proposal is to be submitted.

    (3) At least 2 business days before the board of state canvassers meets to make a final determination on challenges to and sufficiency of a petition, the bureau of elections shall make public its staff report concerning disposition of challenges filed against the petition. Beginning with the receipt of any document from local election officials pursuant to subsection (1), the board of state canvassers shall make that document available to petitioners and challengers on a daily basis.