The state’s top court has ruled that the audio from the custody hearing of a girl who was later killed by her father will be released to a filmmaker.

Essex Juvenile Court has refused to hand over the audio recording of the 2019 juvenile care and protection hearing — during which the custody of 4-year-old Harmony Montgomery was given to her father, Adam Montgomery.

Shortly after the custody decision, Harmony was killed by her father, who has been sentenced to 56 years to life in prison.

Police believe that the 34-year-old man killed Harmony in 2019, and then she wasn’t reported missing for nearly two years. The girl’s body has never been found.

There has been widespread publicity in the wake of the girl’s disappearance and death, along with concerns about the handling of her care and custody by authorities in Massachusetts and New Hampshire. A documentary filmmaker has been trying to shine a light on the custody hearings in Essex Juvenile Court, and now the state Supreme Judicial Court has ruled in his favor.

“We conclude that the journalist has demonstrated good cause for the release of those recordings to him for use in the documentary,” the SJC wrote in its Wednesday ruling. “We vacate the order of the second judge denying the journalist’s motion and order the release of the February 2019 hearing recordings to the journalist.”

“The journalist asserts that the reason for his request is to use the audio recordings of the custody hearings in connection with a documentary concerning the child welfare system,” the justices added. “Releasing these recordings to the journalist for purposes of the documentary he proposes may help to better inform the public both about what happened to this child specifically and whether there are steps the child welfare system generally can take to minimize the possibility of repeating this tragedy.”

The case was brought before the court by LCMedia Productions, Inc., and founder Bill Lichtenstein. He’s filming “Broken,” a documentary that explores the secrecy of Massachusetts’ child protection and juvenile court systems.

“A significant impediment to protecting children in the Massachusetts foster court and juvenile court systems has been their absolute unconditional secrecy,” Lichtenstein said in a statement. “This decision brings sunlight to these vital issues to help protect children and families.”

Adam Montgomery attacked Harmony in the early morning hours of December 7, 2019, police said. He reportedly struck Harmony on her head and face because she had a bathroom accident.

Then, several hours after the first attack, Harmony had another bathroom accident, and Montgomery attacked her again, police said. This assault was far more severe, according to police.

In the two years after Montgomery killed his daughter, he reportedly told witnesses that Harmony’s mother had taken her to Massachusetts and that he was visiting her. Montgomery promised officers that Harmony was alive and well, living with her mother.