Maine county jails may soon have more say about whether to accept some detainees from federal immigration authorities.

Gov. Janet Mills said Wednesday that she supports LD 2058, which lawmakers in both the House and Senate initially passed this week. The bill advanced largely along party lines, with most Democrats voting in favor and most Republicans against.

Lawmakers and advocates say the bill clarifies an existing law that was overbroad and misinterpreted. But the leader of the state sheriffs’ association says he doesn’t fully support new language that was added by the Legislature.

The current law says Maine’s county jails must always be available for people who were “arrested by state or any other law enforcement officers.”

That language has hindered some efforts by protesters who were pushing for Cumberland County commissioners to ban U.S. Immigration and Customs Enforcement from using the county jail in Portland. Sheriff Kevin Joyce, who testified in support of the bill, has said he’s not interested in accepting ICE detainees who only face administrative violations such as being in the country illegally.

But the state’s Department of Corrections has told county leaders that under the current law, a jail can’t turn away any law enforcement agency, including federal immigration authorities, that wants to keep detainees at the facility.

A proposed change to that statute would allow sheriffs to decide whether they want to accept people who were detained solely on civil violations of federal immigration law.

Sen. Rachel Talbot Ross, D-Portland, who sponsored the bill, has told lawmakers that the existing law was “never intended” to require Maine jails to cooperate in civil immigration enforcement, only criminal offenses. She said the bill will “resolve any possible ambiguity.”

She also criticized ICE’s tactics in Maine as agents carried out an enhanced enforcement operation in January, which she called racial profiling. Most of the roughly 200 people arrested during that surge had no criminal convictions or charges, according to information recently released by the Deportation Data Project.

Sen. Scott Cyrway, R-Benton, told his fellow senators Monday that he’s concerned that lawmakers didn’t consult ICE or other federal authorities about how this new language could affect their operations. He described the bill as “putting a wedge” between counties and the federal government.

Before the bill went to the State House floor, lawmakers and law enforcement leaders kicked around ideas that would address the law’s ambiguity without interrupting jails’ current practices.

Several counties rely on funding from federal law enforcement agencies who pay to house detainees at their jails, including ICE, the U.S. Marshals Service, and U.S. Customs and Border Protection.

Michael Kebede, policy director for the American Civil Liberties Union of Maine, said in an interview Wednesday that the bill wouldn’t prohibit jails from working with ICE, but clears up the law’s original purpose.

But some say the change isn’t perfect.

Penobscot County Sheriff Troy Morton, who heads the state sheriffs’ association, said he and Joyce worked with Talbot Ross and other lawmakers to “find common ground” on the issue.

He had supported some amendments to the bill but said he is unsure how the new language will be implemented because federal and local definitions of what constitutes a civil violation are different.

“While revised language was ultimately presented in an attempt to address these concerns, it did not receive full endorsement from the Maine Sheriffs’ Association,” Morton said in a statement Wednesday. “Key questions remain regarding boarding agreements and the lack of clarity surrounding federal civil detainee terminology.”

Morton said the sheriffs’ association is committed to working with lawmakers and other stakeholders to make sure any changes are “clear, workable, and consistent with the operational realities” at Maine’s county jails.

Editor’s note: This story was updated on April 2 to clarify that LD 2058 has only received initial approval from the Legislature.