In Brown v. Smallwood, 153 N.W. 953 (Minn. 1915), the Minnesota Supreme Court considered a preferential voting system similar to IRV and Borda Count. The Supreme Court found the preferential system at-issue in Brown v. Smallwood to be unconstitutional, and stated that a preferential voting system generally would have to be implemented through a constitutional amendment. Id. at 957.

The Supreme Court noted that the preferential voting system at-issue in Brown v. Smallwood violated Minn. Const. Art. VII, §§ 1 and 6 (1915). Id. at 955-956. [N.B. Minn. Const. Art. VII, § 6 (1915) is now Minn. Const. Art. VII, § 5 (2005)]. The Supreme Court addressed the concerns of a preferential voting system by stating the following:

The preferential system directly diminishes the right of an elector to give an effective vote for the candidate of his choice.  If he votes for him once, his power to help him is exhausted. If he votes for other candidates he may harm his [first] choice, but cannot help him. Another elector may vote for three candidates opposed to him. The mathematical possibilities of the application of the system to different situations are infinite.

Brown v. Smallwood, 153 N.W. 953, 956 (Minn. 1915).

In conclusion, the City of Minneapolis appears to be able to provide for a new voting method by charter amendment pursuant to MINN. STAT. § 410.21 (2005), but the City of Minneapolis appears to be precluded from adopting a preferential voting system generally unless such a system is provided for by the Minnesota Constitution pursuant to Brown v. Smallwood, 153 N.W. 953, 957 (Minn. 1915).