Adam Montgomery killed his daughter Harmony in a gruesome murder. Here’s everything we know

Adam Montgomery has never admitted that he killed his five-year-old daughter Harmony.

Although her life was short, documents show that Harmony Montgomery endured an extraordinarily difficult childhood. Her mother struggled with substance abuse issues, meaning Harmony bounced in and out of foster homes — until she was put in the custody of her father in February 2019.

Despite having a violent criminal history and spending only 40 hours across 20 supervised visits with his daughter from the time she was born to age four and a half, he was awarded custody.

Around 10 months later, she was dead.

She slipped through the cracks of the systems in place across two states, with agencies missing crucial safety and background checks, begging the question of whether Harmony would still be alive today had those systems not failed her.

To add insult to injury, authorities didn’t start looking for her body until two years after she died.

It wasn’t until December 2021 that Montgomery was charged with second-degree assault. One year after that, in October 2022, he was charged with murder.

During Montgomery’s trial, his defence attorney insisted that while Montgomery “did horrible things” to hide Harmony’s body, he did not kill her.

After all this time, Montgomery has still maintained his innocence in the death of his daughter.

But the New Hampshire jury didn’t buy it, finding the father guilty of second-degree murder in February.

Now, on May 9, he is scheduled to appear in court for his sentencing.

The day of the murder

Most of the revelations of the case stemmed from Kayla Montgomery’s testimony.

Kayla, Adam’s estranged wife, had already been sentenced to 18 months in prison on perjury charges for initially lying to law enforcement regarding Harmony’s whereabouts.

Although the defence team tried to paint Kayla as a “liar,” the prosecution argued that she was afraid of disclosing the truth because she was being abused and threatened by Adam Montgomery.

“Adam was getting really angry from Harmony peeing in the car, and he repetitively kept punching her on the way to Burger King,” Kayla told jurors while sobbing.

She said when they stopped driving at red lights, Adam “would go over the driver’s seat in between the passenger seat, and he was just punching her repetitively in the head.”

Harmony’s body was moved several times, Kayla told the court.

The five-year-old’s corpse was first stored in a cooler at Kayla’s mother’s home. Then it was relocated to a ceiling vent at a shelter the family had lived in.

“He compressed and contorted her body into this bag,” the prosecution said at his murder trial while showing a medium-sized tote bag.

Prosecutors said that when investigators scoped out the room two years later, they saw deep blood stains in the ceiling vent and smelled decomposition.

“And surrounding Harmony’s blood, all that was left of her .... the defendant’s fingerprints and palm prints, froze in there for a time,” the prosecution said.

Neighbours started to complain about the smell, prosecutors said during the trial. So, Montgomery then began bringing Harmony’s remains to work with him every day; he then worked as a cook and dishwasher at the since-closed Portland Pie Company.

“[The bag] stood out to people, because he placed it in the freezer during his shifts,” a prosecutor said. “He brought it with him regularly to work and he stored it in a freezer where the company kept food and ingredients. People saw him bringing that in and out. They couldn’t have imagined what that bag contained.”

How Montgomery allegedly disposed of the body

Montgomery started his efforts to destroy his daughter’s body in March 2021, Kayla testified.

As Kayla’s testimony continued, the details became even more gruesome.

She recalled Montgomery discussing using a handsaw, lime and even a NutriBullet to destroy Harmony’s rotting remains.

Montgomery spent hours inside the bathroom “dethawing” Harmony’s frozen remains, cutting the clothes off the body, and running hot water on to what remained of the little girl, Kayla testified.

“He wanted to use a handsaw and a NutriBullet,” Kayla told the court. “He said that’d be good to use to help get rid of her ... I saw Harmony folded together the same way she was when we took her out of the car. She looked like she had barely any skin, just skin and bones and was very bruised. He had the hot water running ... in the tub.”

It’s unclear whether he actually went through with the Nutribullet plan. However, Kayla testified that he had a “large” bag of lime in the bathroom.

“He said that he wanted to get rid of the body soon because he was scared of anything that could happen to him and the kids,” she told the court.

Montgomery asked Kayla to help him with his efforts to destroy his daughter’s remains, she testified, but she didn’t go through with it.

At some point, she said, Montgomery placed the remains back in the tote bag and inside the freezer again.

The child’s remains have never been found.

Arrested and charged

In January 2022, Adam and Kayla Montgomery were indicted in New Hampshire.

Adam was accused of second-degree assault for hitting his daughter in the face while Kayla was accused of theft by deception for fraudulently obtaining $1,500 in food stamp benefits meant for Harmony between December 2019 and June 2021, despite the fact that the little girl was not living with her.

In April 2022, both Montgomerys faced unrelated charges related to the theft of firearms.

Months later, in June, Kayla was arrested for perjury charges. She told a grand jury that she was working at the time when Harmony was last seen alive.

Speaking to authorities in June, court documents show that she accused her husband of murdering his daughter. The filing said that Kayla divulged to police that Adam had encouraged her to lie about Harmony’s whereabouts, “basically giving Kayla a ‘cover story’ and telling her that as long as she stuck to the cover story everything would be OK.”

It wasn’t until October of that year that Adam faced murder charges.

One month later, in November 2022, Kayla pleaded guilty to perjury charges.

In exchange, she agreed to testify at her estranged husband’s murder trial.