With an April 27 deadline for overseas absentee ballots to be delivered to voters, Maine continues to wrestle with how to implement the elections system approved by voters in November 2016.

In ranked-choice elections, voters choose multiple candidates in order of their preference. If no candidate garners more than 50 percent of the total vote, the last-place finisher is eliminated and the second choices of voters who cast ballots for that candidate are used in a retabulation. The process repeats until a winner emerges with a majority of the votes.

Here is a brief history of how ranked-choice voting in Maine went from a series of failed proposals to citizen-initiated law to a source of legal controversy:

June 3, 2009: The Maine Legislature kills a bill sponsored by then-Rep. Diane Russell, D-Portland, that would have established a ranked-choice voting pilot project in several Maine municipalities.

March 7, 2011: After a three-year study, the League of Women Voters issues a position statement endorsing ranked-choice voting in single-seat elections.

June 9, 2011: Another Russell bill — this time to use ranked-choice voting in gubernatorial elections — dies after a legislative committee unanimously votes it down.

June 11, 2013: A bill to establish a ranked-choice voting system in state elections from then-Sen. Dick Woodbury, I-Yarmouth, fails after 90-57 and 20-13 votes against it in the House of Representatives and Senate, respectively.

January 2016: Secretary of State Matthew Dunlap and Attorney General Janet Mills, both Democrats, flag what they see as constitutional issues with a citizen-initiated proposal to implement ranked-choice voting.

Nov. 8, 2016: Following a citizen-initiated petition to put the question on the ballots, approximately 52 percent of Maine voters approve implementing ranked-choice voting for gubernatorial, congressional and legislative races.

Dec. 7, 2016: Gov. Paul LePage proclaims the results of the referendum valid.

Feb. 2, 2017: The Maine Senate votes 24-10 to ask the Maine Supreme Judicial Court to develop and issue an opinion on the constitutionality of ranked-choice voting.

May 23, 2017: The Maine Supreme Judicial Court releases an advisory opinion that part of the ranked-choice voting law is unconstitutional because of a reference in the Maine Constitution referring to elections being won by pluralities, which means whoever receives the most votes. The 44-page decision was unanimous.

Oct. 24, 2017: After months of debate about bills to repeal or continue ranked-choice voting that resulted in partisan gridlock, the Legislature enacts a bill that put off the implementation of ranked-choice voting until the Maine Constitution can be amended to accommodate it. The bill includes a provision that would nullify ranked-choice voting if that doesn’t happen prior to December 2021.

March 5, 2018: A people’s veto petition seeking to nullify the Legislature’s law to delay implementation is certified by Secretary of State Matthew Dunlap. That sets the stage for ranked-choice voting to be implemented in time for the June 12, 2018, primary election, but also sets up a referendum in that election to repeal the law passed by the Legislature in October 2017.

March 29, 2018: Secretary of State Matthew Dunlap drops a bombshell when he announces that a legislative committee analyst found a discrepancy in current Maine law that calls for a plurality to win in one place and a ranked-choice majority in another. Dunlap says that because of deadlines to print and deliver ballots, he will move forward with implementation.

April 2, 2018: Following a contentious debate, the Maine Senate votes to authorize Senate President Mike Thibodeau the temporary authority to intervene legally in current and future suits involving ranked-choice voting.

April 3, 2018: On behalf of the Senate, Maine Senate President Mike Thibodeau files court papers requesting “ expedited review by the Maine Supreme Judicial Court” of potential constitutional problems with the ranked-choice voting law before the June 12, 2018, elections.

April 4, 2018: Maine Superior Court Justice Michaela Murphy issues a temporary injunction ordering Secretary of State Matthew Dunlap to move ahead with implementation of ranked-choice voting for the June 12, 2018, elections. Proponents of the system and eight gubernatorial candidates had sought the ruling.

April 11, 2018: Maine Superior Court Justice Michaela Murphy formally asks the Maine Supreme Judicial Court to rule on seven questions related to the Maine Senate’s petition to the courts.

April 12, 2018: The Maine Supreme Judicial Court meets to hear new arguments on the constitutionality of ranked-choice voting.

Compiled by Christopher Cousins and Michael Shepherd.

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