CONCORD, N.H. (Court TV) — A New Hampshire teen pleaded guilty to the murders of his sister-in-law and two nephews on Friday.
In a naked plea agreement, 19-year-old Eric Sweeney pleaded guilty to three counts of second-degree murder and a charge of falsifying physical evidence.
Eric Sweeney, accused of killing his sister-in-law and two young nephews when he was 16, enters court on Friday, Aug. 15, 2025 at Merrimack County Superior Court in Concord, N.H. (Geoff Forester/ Concord Monitor via AP, Pool)
A naked plea agreement means prosecutors did not make any agreement regarding sentencing.
In court on Friday, Assistant Attorney General Bethany Durand said Eric killed Kassandra Sweeney and her sons, 4-year-old Benjamin and 23-month-old Mason, on August 3, 2022. At the time of the killings, Durand said Kassandra and her husband, Sean Sweeney, were guardians of then-16-year-old Eric.
Durand said the couple had called police twice in the months and weeks before the murders about Eric. The first time was to report that he took their vehicle without permission. The second call was to report he was making “strange statements,” said Durand.
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On Aug. 3, 2022, Police responded to the scene after Sean called 911 to report his brother had called him from Kassandra’s phone and said someone had broken into the house and “killed everyone.” Inside the home, police found the bodies of Kassandra and Mason in the dining room. Benjamin’s body was found in the kitchen. Each victim died from a single gunshot wound. Investigators said there was no evidence of forced entry or burglary at the home, like Eric had told his brother.
During an initial police interview, Eric told investigators he was in the basement when he heard a “deep male voice” and gunshots before discovering the victims. He then took Kassandra’s Ford F-150 and left the home without seeking help. Durand said he placed the first call to Sean 17 minutes later, not reaching him until 20 minutes after leaving the scene.
Investigators determined Eric used his brother’s Taurus .40 caliber handgun in the killings and disposed of the firearm on a highway. No motive has been revealed. Durand described multiple videos and pictures Kassandra had sent Sean in the minutes leading up to the murders that indicated “the family was having a normal morning.”
At the time of his arrest, he was charged with three counts of first-degree murder in addition to falsifying physical evidence.
Other terms of the plea agreement include that Eric should have no contact with any family members except his mother. Eric also cannot profit from anything produced about the case.
Eric faces life in prison at his sentencing set for October 3.
