Lawmakers heard testimony Tuesday on a proposed constitutional amendment that would create an independent commission to draw boundaries for state elections.

Current law leaves the responsibility of redistricting to the New Hampshire Legislature. Supporters of this measure say that allows for gerrymandering, or the ability of the majority party to draw boundary lines in its favor.

Democratic State Rep. Ellen Read, a supporter of the measure, said she's mentioned limiting gerrymandering to members of her party in the past.

"And this person within my own party said, 'Oh no you don't, the other guys did it, so we're going to do it to them when it’s our turn,'” Read said.

This bi-partisan-backed update to the state constitution would set up a seven-member commission made up of members of the public. “The President of the Senate, the Speaker of the House of Representatives, and the minority leaders of the House of Representatives and the Senate shall each appoint one member,” the measure reads. The remaining three members would be selected by the initial four appointees, in a process administered by the Secretary of State.

Several voters as well as members of progressive groups in the state spoke in favor of the proposed constitutional amendment.

"Demand an end to gerrymandering and restore the confidence not only in the sanctity of the vote -- that there are fair districts being created -- but also restore the confidence in the legislature," said Liz Tentarelli, President of League of Women Voters of New Hampshire, a non-partisan coalition that advocates for voting rights.

Yurij Rudensky, Redistricting Counsel at the Brennan Center for Justice, a non-partisan group that has advocated for redistricting reform, said he’d worked closely with the amendment’s sponsors to “make sure that these proposals advance best redistricting practices.”

Rudensky recommended that lawmakers update the amendment so that the commission would have at least nine members. “It worries me that there are only two Democrats and only two Republicans and three unaffiliated members,” Rudensky said. “We heard from jurisdictions like Arizona, Washington state that use small commissions -- that use five member commissions -- that a slightly larger one in many instances would make it easier to reach compromise and work because there were times when there was one obstinate member.”

Other states, including California, Arizona and Washington have adopted independent redistricting commissions.

“Courts provide a robust backstop against unfair and unconstitutional legislative maps, and judges have recently not hesitated to strike down maps that truly create an uneven playing field,” Governor Sununu’s spokesman Ben Vihstadt said in an email. “Governor Sununu believes the current system works well.”

For passage, a proposed amendment to the New Hampshire Constitution needs a three-fifths margin of approval in the Senate and House. If one meets that threshold, it is passed directly to the voters for ratification, where voter approval needs a two-thirds vote.