New Hampshire Supreme Court overturns Adam Montgomery's second-degree murder conviction

The New Hampshire Supreme Court on Thursday reversed the second-degree murder conviction of Adam Montgomery, who was sentenced in 2024 to 56 years to life for the death of his five-year-old daughter, Harmony. The justices ruled that the murder and assault charges should have been tried separately, finding that the combined trial risked jurors being unduly influenced by the stronger assault evidence.

The court affirmed Montgomery's convictions for falsifying physical evidence, witness tampering and abuse of a corpse, which remain in effect. In its opinion, the court stated that the misjoinder of offenses was not harmless with respect to the homicide charge and therefore required reversal of the murder conviction.

Former assistant attorney general Jesse O’Neill, who worked on the case, said, > "It was a tough decision to read, but it’s the job of our courts, specifically our Supreme Court, to make sure things are done right, and fairness is maintained."

Montgomery's legal team had argued that the trial should have separated the assault and murder charges, excluded testimony from his daughter’s mother, Kayla Montgomery, and barred police body-camera video. The state had contended that any error in joinder was harmless because the evidence of guilt was overwhelming, a position the justices rejected.

The ruling leaves open the possibility that the state may seek a new trial on the murder charge or file a motion to reconsider the decision. Montgomery remains incarcerated on the other convictions while the murder case is pending further action.