The New Hampshire Supreme Court has overturned the murder conviction of Adam Montgomery in the death of his 5-year-old daughter, Harmony Montgomery.
Montgomery was convicted in 2024 on second-degree murder charges for killing his daughter in 2019, and on second-degree assault for earlier physical abuse against her. But in a ruling Thursday, the state's high court voided the murder conviction, finding that Hillsborough County Superior Court Judge Amy Messer improperly allowed jurors to weigh Montgomery’s murder and assault charges together during the same trial.
In his appeal, Montgomery argued that his separate murder and assault charges should have been considered separately. The state, meanwhile, argued that considering multiple charges during a single trial did not affect the trial’s outcome or impair Montgomery’s rights.
Thursday’s ruling affirmed Montgomery's second-degree assault conviction, but reversed the second-degree murder conviction, sending the case back to Superior Court.
“Trying the second-degree assault and second-degree murder charges in a single trial jeopardized the defendant’s right to a fair trial,” the Supreme Court justices wrote.
Montgomery, who is in a Virginia prison, was sentenced to 56 years to life on the murder charge. He is also serving a minimum 32-year sentence for prior firearms convictions.
In a statement, the New Hampshire Attorney General's Office said it will seek a retrial of Montgomery for second-degree murder.
"We remain confident in the facts of this case, the evidence presented, and the exceptional work of our prosecutors, investigators, and law enforcement partners,” the statement said. “We will continue our efforts to seek justice for Harmony Montgomery and all those who knew and loved her."
Earlier this year, a judge issued a $15.5 million judgment against Montgomery in a wrongful death lawsuit brought by the mother of Harmony Montgomery.