During the spring and summer of 2012, Minnesota's attention was focused on a variety of issues being voted upon in the upcoming elections in November 2012, including the contest between presidential candidates and the many races which would determine control of the Minnesota legislature. One of the highest profile MN campaigns was that waged by Minnesotans United against the proposed constitutional amendment which would ban same-sex marriage.

Far less attention was being paid by the public to what was initially a lower profile contest in which an amendment was being proposed to the Minnesota Constitution to require voters to present a valid state issued picture identification at polling places before being allowed to vote—what came to be known as the "Voter ID amendment." Although polls had consistently shown that voters approved the proposed Voter ID amendment by a margin of more than 80%, many in the state, including the League of Women Voters and Common Cause, opposed the Voter ID amendment on multiple grounds.

At the request of the American Civil Liberties Union of Minnesota, Maslon partner and ACLU-MN board member Bill Pentelovitch undertook representation of the League of Women Voters, Common Cause, Jewish Community Action, and several voters in a challenge to the placement of the proposed Voter ID amendment on the ballot. Under Minnesota law, such challenges are filed directly in the Minnesota Supreme Court, which hears and decides such matters on an expedited basis.

Bill, with the assistance of Maslon attorneys Rich Wilson and Catherine Ahlin-Halverson as well as former Maslon attorney Wayne Moskowitz, put together the petition to the Supreme Court and necessary briefs during June, and Bill argued the case before the Supreme Court in July. In addition, on behalf of Common Cause, Jewish Community Action, the ACLU-MN, and several individuals, Bill and the Maslon team filed an amicus curiae brief in the Minnesota Supreme Court in a separate action which had been commenced challenging the Secretary of State's selection of a title for the Voter ID amendment on the ballot.

Although the Supreme Court ruled against Maslon's clients in both cases, each decision drew vigorous dissents by Justices Paul Anderson and Alan Page. Maslon's brief, together with those dissents, framed the public discourse about the Voter ID amendment during the final two months of the campaign. Bill Pentelovitch participated in several forums debating the amendment against its proponents.

Ultimately, Minnesota voters soundly rejected the Voter ID amendment. For his efforts, Minnesota Lawyer named Bill Pentelovitch one of its 2012 Lawyers of the Year.