An anti-gerrymandering group is warning that Utah’s legislative leaders are poised to dismantle a voter-approved law on redrawing the state’s political boundaries.

“This is the literal definition of the fox guarding the henhouse," Jeff Wright, co-chairman of Better Boundaries, a bipartisan group that supported the initiative, said Friday morning in a prepared statement. “If the Utah Legislature eliminates the core principles of gerrymandering reform, they are missing the point.”

Legislators, on the other hand, say they and Better Boundaries arrived at an accord on a majority of the proposed changes to the Proposition 4 law — clashing only over whether the law should strictly prohibit the redistricting commission from gerrymandering and protecting incumbents. Given these points of agreement, Senate Majority Leader Evan Vickers charged Better Boundaries with going “a little bit nuclear” by issuing a Friday news release predicting an attempt at outright repeal.

Prop 4, approved narrowly by voters in 2018, would create an independent commission appointed by the governor and legislative leaders to draw Utah’s congressional and legislative districts after the census every 10 years. The Legislature would have the ability to reject the proposed map but would have to explain its reasons to voters.

Republican leaders in the Legislature resisted the initiative, arguing that the Utah Constitution gave them the sole responsibility for redesigning voting districts.

Now, Better Boundaries says it’s clear state lawmakers are intent on undermining Prop 4 by rejecting some of the law’s central anti-gerrymandering provisions. Specifically, Rebecca Chavez-Houck, a former state representative and executive director of Better Boundaries, said lawmakers are thinking of stripping out a ban on drawing districts purposefully to favor or disfavor an incumbent or political party.

“The ban is the heart of Prop 4,” Chavez-Houck said Friday.

The language of the anticipated rollback bill isn’t publicly available, and Chavez-Houck said her group has seen drafts but not final language. Better Boundaries has been negotiating for more than a year with legislators over the redistricting law, she said, but the talks broke down when GOP leaders refused to keep the ban on partisan gerrymandering.

Sen. Curtis Bramble, who’s sponsoring the forthcoming bill on Prop 4, said the ban was problematic because the negotiators were unable to craft a good definition for gerrymandering, raising concerns that the state would have difficulty proving compliance if someone sued over their voting maps.

“We asked for a clear definition ... of the term ‘gerrymandering’ for the purposes of state statute,” the Provo Republican said. “They could not provide that definition."

Vickers, R-Cedar City, said the seven-member independent commission could’ve developed its anti-gerrymandering rules, as long as the ban wasn’t baked into state law.

Bramble said his legislation would address this issue and scrap a requirement that the Legislature either reject or accept the commission’s proposed map. The bill, he said, will also delete sections giving the chief justice of the Utah Supreme Court a role in selecting a map recommendation if the commission fails to adopt a version by the mandated deadline.

He said he wouldn’t personally favor a wholesale repeal of Prop 4.

Chavez-Houck confirmed that, in a painful concession during the negotiations, her group was willing to let go of the Prop 4 requirement that the Legislature vote up or down on the commission’s map. With the proper safeguards in place, the independent commission’s design would still have value as a foil to whatever version the Legislature passed, she said.

But if the public can’t trust the commission to refrain from protecting incumbents or serving political interests, she warned, the whole system of checks collapses.

Gerrymandering is a difficult term to define, Chavez-Houck acknowledged, but she said Better Boundaries shared various methods of analysis that other states have used to detect partisan bias in their voting maps. The group suggested referencing those tools in state law or simply offering them to the commission as a way to evaluate their district designs, but to no avail, she said.

House Speaker Brad Wilson, R-Kaysville, said lawmakers had been working with Better Boundaries to address what legislative leaders perceive to be constitutional issues with the anti-gerrymandering initiative. He said lawmakers would prefer to have a willing partner in that effort but will move forward with or without Better Boundaries’ involvement.

“We haven’t completely decided on a course of action yet,” he said.

Wilson suggested the independent redistricting commission would survive but that the restrictions placed on it would be loosened to allow commission members to determine their own approach to drawing new maps for the state. He said the anti-gerrymandering law would be “tweaked” but would largely remain intact.

Wilson said the process of drawing voter maps is designed to be political. He noted that the states current maps were adopted with bipartisan majorities and suggested that the requirement that voting districts be equal in population works as a check against bad-faith efforts.

“I would hope that we do what’s in the best interest of the state, and gerrymandering is not something that we see happening in a significant way,” Wilson said. “It is a lot harder to do than it sounds.”

Alliance for a Better Utah, a group that advocates for progressive policies in the state, denounced attempts to repeal or weaken Prop 4 as a “blow to democracy.”

“Not only are GOP lawmakers once again expressly overturning the will of the people, they are now attacking the principle that voters should choose their representatives, not the other way around,” Chase Thomas, the alliance’s executive director, said in a prepared statement.

State lawmakers have already made drastic changes to two other voter initiatives passed in 2018 — one to allow medical cannabis in the state and another on Medicaid expansion. Critics of those decisions have taken the Legislature to task for ignoring the will of voters as expressed through the initiatives, but Bramble argued the changes he’s supporting could actually protect Prop 4.

“There’s a school of thought that by making these amendments, it actually strengthens the prospects of maintaining this commission rather than having it be thrown out on constitutional grounds,” he said.

Chavez-Houck defended the constitutionality of Prop 4.

“We wouldn’t have been able to get it on the ballot if it weren’t,” she said.