Hawaii voters in Tuesday’s general election will decide whether to convene a state constitutional convention. It’s been 40 years since the last one.

The ballot measure is put to a vote every 10 years. If it passes, delegates will be chosen during the next election or a special election called by the Legislature. Any amendments arising out of the convention would need to be approved by voters.

A simple majority of votes is required for the measure to pass, though blank votes will be counted as “no” votes.

The last convention, in 1978, included more than 100 delegates who met for three months and ultimately put forward 34 proposed amendments. The convention resulted in the passage of major environmental protections, created the Office of Hawaiian Affairs, recognized Hawaiian as an official state language and created term limits for the office of governor, among other changes.

Preserve Our Hawaii, a diverse and powerful coalition made up of unions, businesses and environmental groups, is urging residents to vote “no” on whether to hold a state constitutional convention. The coalition includes many of Hawaii’s major unions, such as the Hawaii Government Employees Association, and unions representing public school teachers, police and firefighters. The Chamber of Commerce of Hawaii, the Sierra Club of Hawaii and the Hawaii chapter of the American Civil Liberties Union have also joined in the coalition, as has the Hawaii Democratic Party. The party’s state central committee voted unanimously to oppose a convention.

The organized opposition from groups that could stand to lose something if the state Constitution is altered mirrors efforts made the last time the question was posed to voters. In 2008, groups opposing what is commonly referred to as a ConCon spent $1.4 million, according to the Hawaii Campaign Spending Commission. By contrast, ballot measure committees supporting a convention spent just $6,000. The convention was defeated 62 percent to 34 percent, with about 4 percent of voters leaving the question blank.

There hasn’t been a comparable, organized effort to drum up support for a constitutional convention, though individuals such as state Sen. Laura Thielen have publicly expressed their support.

Opponents of a convention have argued there is too much at stake to open the state Constitution to revision, particularly when it comes to protections for labor, the environment and Native Hawaiians. Some have also worried that money and special interests could unduly influence a convention.

Proponents have argued the state Constitution was meant to be periodically revised, and that a convention could help restore trust in government and provide an opportunity to push forward reforms the Legislature has been reluctant to take up, such as campaign finance reform and establishing term limits for state legislators.

Skip tax question

Voters were also poised to decide this year whether to amend the Hawaii Constitution to allow the state to tax property to support public education. However, the Hawaii Supreme Court invalidated the question last month, agreeing with Hawaii’s four county governments that the wording of the question wasn’t sufficiently clear. Hawaii law requires the language of a proposed constitutional amendment be “neither misleading or deceptive.”

The question will still show up on ballots, which had already been printed when the Supreme Court issued its ruling, but any votes cast for or against the measure won’t count.

The counties as well as an array of powerful business interests had opposed the constitutional amendment.

Its major backer, the Hawaii State Teachers Association, had hoped that if it passed the Legislature would then act to tax second homes valued at $1 million or more. The HSTA argued that more revenue is needed to boost teacher salaries and better fund classrooms.