Minn. Stat. § 372.03

At the time and place specified in the notice, proof of its service having been filed, the county board shall meet to act on the petition. The board shall inquire and determine if any of the petition signatures are not genuine; the signers were not, at the time of signing legal voters of the county; the signatures were not attached within 60 days before the filing; and if any of the signatures have been withdrawn. All such signatures shall be stricken from the petition and deducted from the count, and a list, certified by the board, shall be filed with the auditor. Any competent evidence offered bearing upon the matters committed to the determination of the board shall be received; and any voter of the county may appear, in person or by counsel, and be heard in respect to these matters, under reasonable rules as the board may prescribe.