AUGUSTA (AP) — Open records advocates won a big victory in 2013 when Maine’s highest court paved the way for more 911 transcripts to be released to the media. A year later, officials said they would move to make some emergency call information secret again.

It would be another example of how the Legislature has chipped away at the Freedom of Access Act hundreds of times since its adoption.

When Maine’s public records law was passed in 1959 — nearly a decade before the right to public openness was codified in federal law — all records were considered open as long as they were used in public or governmental business.

This session, lawmakers will consider adding several exemptions to the law on top of the roughly 500 already on the books.

“It’s the constant battle that we have — to weigh public interest against private interest,” said Mal Leary, vice president of the Maine Freedom of Information Coalition and managing editor and director of the Maine Capitol Connection.

“We always have to be vigilant,” he said.

Among the new proposed exemptions are efforts to make records confidential if they describe materials transported by trains or contain personal information about library patrons.

And then there are those 911 transcripts: The Department of Public Safety said two months ago it will press for allowing officials to withhold certain information from 911 calls about victims of domestic violence and sexual assault. A draft for the bill has not yet been released.

In 2013, the Maine Supreme Judicial Court ordered that the Portland Press Herald be provided 911 transcripts in the case of a 75-year-old man charged with killing two teens, rejecting the state’s argument that doing so would harm their investigation.

The court’s decision didn’t call for the release of all 911 transcripts, but open records advocates said the ruling would make it more difficult for officials to withhold them in the future.

Sigmund Schutz, a lawyer who represented the Press Herald, said any effort to further restrict access to 911 calls could inhibit the public from holding law enforcement officials accountable.

Details about the department’s proposal have not been released and its spokesman declined to comment. A spokesman for Republican Gov. Paul LePage also refused to discuss the administration’s proposal.

Margo Batsie, justice coordinator for the Maine Coalition to End Domestic Violence, said releasing some information can harm prosecution efforts and victims as they recover.

“I don’t think it’s beneficial to the public discourse to hear someone at their most vulnerable,” said Batsie, whose group supported a bill in 2013 that would have allowed law enforcement to withhold all 911 transcripts related to a pending investigation or prosecution. The measure was killed in the Legislature.

Open records advocates acknowledge that many exceptions were carved out in the law for good reason — whether it’s to protect against the release of a person’s medical information or details about a criminal investigation.

But other restrictions seem to have little purpose other than to serve special interest groups, Leary said. He pointed to a law that makes information about growing ginseng in Maine confidential.

When that exemption was passed in 1996, the agriculture department argued it was to protect against theft because ginseng is a high-value crop that is often planted in remote locations.

Rep. Michael Shaw wants to shield records that describe what materials are being transported on railroads when the information is being reviewed by law enforcement or fire officials.

The companies don’t currently provide those documents to first responders because they fear it will end up in the hands of their competitors, he said. Providing that exemption will ensure that first responders get the information they need to do their jobs safely in the event of an accident, he said.

“I’m a big supporter of (freedom of access) … but in this case, we do have people that are risking their lives,” he said.