The St. Paul city attorney's office is offering this advice to City Council members: Avoid instant-runoff voting.

A 10-page opinion released by the office Wednesday lays out an argument that says the voting method would more than likely violate the Minnesota Constitution.

The document also assures the council that it is not obligated to place a question asking voters whether they would prefer the new system on the November ballot -- despite a recently certified petition seeking to do so.

While the council has yet to decide how to address the issue, the opinion in essence frees it to act as it sees fit.

The ballot question would ask St. Paul voters whether they want a system that ranks mayoral and City Council candidates in order of preference and eliminates some September primary elections. The method would only be used in the municipal elections.

The Better Ballot Campaign, which is pushing for the change, submitted 7,168 names two weeks ago. The total number of verified signatures was 5,386; 5,098 were needed.

City Attorney John Choi acknowledged that the opinion is a "best guess" at what a court might find. "We don't have a crystal ball," he said.

Also, the opinion is advisory, so the council could choose to ignore it.

Council President Kathy Lantry said the matter will be discussed.

"If you sink a lot of money into a system you can't use, does it make sense?" she asked.

The Better Ballot folks were still digesting the opinion Wednesday evening.

"Today's opinion clearly provides our elected officials some options -- as well as some opportunities -- for leadership," said Amy Brendmoen, the group's spokeswoman. "As our City Council members consider how they will proceed, we challenge them to find a way to accommodate the voices of their constituents."

She noted that the petition was filed "on behalf of nearly 7,000 St. Paul petition-signers who want progressive election reform."

Citing past Minnesota Supreme Court rulings, the opinion says the council is authorized to keep a question off the ballot if the question is unconstitutional and would result in a "futile election and a total waste of taxpayers' money."

Minneapolis voters adopted the system in 2006, but it's not in place yet. A lawsuit filed by the Minnesota Voters Alliance, an opposition group, is pending.

Minnesota's attorney general last year noted problems with instant-runoff voting but stopped short of calling it unconstitutional.

A 1915 state Supreme Court case said a voting system in Duluth that ranked a voter's choices was unconstitutional. While some instant-runoff supporters say their method is different from the Duluth version and shouldn't be considered in the same way, Choi's opinion said the method wasn't the point. Any alternative voting system would be unconstitutional, he said, because a constitutional amendment would be required for the change.

The opinion also said conflicting legislation keeps the city from establishing its own voting system for general elections.

"I think it's an excellent document," Andrew Cilek, president of the Minnesota Voters Alliance, said of the city attorney's opinion.

Instant-runoff voting requires voters to rank candidates in order of preference. If no candidate gains a majority, the candidate with the least amount of support is dropped and the second-place votes cast by supporters of that candidate are added to the remaining candidates. The process continues until one candidate gains a majority.

Proponents say it ensures a candidate wins by a majority and puts more candidates in front of more voters because turnout is higher at general elections. They also say it saves money because it eliminates primaries.

Opponents say it gives people more than one vote. They challenge the constitutionality of instant-runoff voting and say it limits debate by eliminating primaries.

Ramsey County elections manager Joe Mansky has sent several letters to the council outlining potential problems with the system, including higher costs, lack of certified voting equipment and contrasting procedures because county and school board elections wouldn't use instant-runoff voting.

Said Choi: "It's up to the City Council to do the right thing."

Chris Havens • 651-298-1542