CONCORD, NH – Eric Sweeney pleaded guilty Friday to killing his sister-in-law and his two young nephews, shooting all three in the head in their Northfield home in August 2022.
Sweeney, now 19, entered the pleas before Judge John C. Kissinger Jr. in Merrimack County Superior Court after the state summarized the evidence they would have been presented had the case gone to trial. He was 16 at the time of the killings but was certified by the court to stand trial as an adult.
He also pleaded guilty to falsifying physical evidence for tossing the murder weapon, a .40 caliber Taurus pistol, out a truck window into the median strip of Interstate 93. The gun was later recovered by investigators.
The plea is what is known as a “naked plea,” in that a sentence has not been negotiated with prosecutors. A second-degree murder conviction carries up to life in prison.
Assistant Attorney General Bethany Durand Sean Sweeney told the judge that Sean Sweeney and his wife, Kassandra, had custody of his brother since June 2019. In the months leading up to the killings, Eric had increasing behavioral issues creating tension between he, his brother and sister-in-law, resulting in police being called to their Northfield home. At the time of the murders, Durand said the brothers were barely speaking to each other, she said.
On the morning of Aug. 3, 2022, Eric, using Kassandra’s cell phone, called his brother to say someone had broken into the house “and killed them all,” Durand said. Sean Sweeney called police and headed back to his house.
When police arrived at the 56 Wethersfield Drive home, an officer looked through a window to see a woman and young child – Kassandra, 25, and Mason, 23 months – in pools of blood on the dining room floor. Steps away on the kitchen floor, police found Benjamin, 4, dead. A bullet hole was visible in the hood of the dinosaur costume he was wearing.
Investigators found no evidence of a home invasion.
Autopsies determined all three had died from a single gunshot to the head. The medical examiner recovered a bullet from Kassandra’s body while the bullets that killed the children had passed through their bodies.
Investigators recovered bullet casings, bullet remnants and bullets from the house. The medical examiner determined the bullets came from the .40 caliber Taurus pistol recovered by police.
Sean Sweeney told investigators he kept two guns in a locked safe under his bed but he didn’t think Eric knew that. One was a .40 caliber Taurus pistol, loaded with mismatched ammunition, and the other a 9mm Hi-Point. There were two sets of keys, one in the bedroom closet, the other on the key chain for Kassandra’s Silver F-150 pickup truck.
The Taurus pistol wasn’t there.
That morning, Durand said, Sean Sweeney had left early for work. Kassandra communicated with him through cell phone, sending texts and videos of the children “engaging in playful behavior” with her. One video was of a groundhog outside in the yard, which the kids called a hedge hog. Another recorded Mason, in his dinosaur costume, saying how much he loved his brother.
Through those texts and videos, investigators were able to pinpoint the time when the murders took place – around 11 a.m. – because Kassandra sent four Snapchat messages at 10:58 a.m., the last time she did.
Minutes later, investigators tracked movement of Kassandra’s phone heading away from the home. Eric Sweeney took Kassandra’s cell phone with him when he left in Kassandra’s pickup truck, authorities said, the same truck recorded on one of the videos she sent her husband.
Eric drove down the driveway passing tree workers, never stopping, and continued driving until he reached Interstate 93 South where he threw the murder weapon out the window into the median strip.
At 11:16, he tried to call his brother but the call didn’t go through. At 11: 17, he texted his brother, “Help.” Seconds later, he sent a second text, “It’s Eric.” He finally connected with his brother in a call at 11:19 a.m. when Eric tells him someone broke into the house and “killed them all.”
When he later spoke with investigators from the New Hampshire State Police Major Crime Unit, Eric denied committing the murders. Sean Sweeney, who was present during the interview, collapsed on the floor, Durand said.
Investigators also found gunshot residue on Sweeney’s hands and on the steering wheel of the pickup truck.
Sentencing is set for Oct.3. Attorneys are to file sentencing memorandums, arguing for what they believe Sweeney deserves as a sentenced, by Sept. 26.