Woman pleads guilty to 2nd-degree murder in death of former longtime partner

Haydee Rivera-Nadeau during her plea hearing in Strafford Superior Court on Thursday; inset, Lisa Rocheleau (The Rochester Voice photo; Rocheleau courtesy)

DOVER - She could barely stand, and her voice was often inaudible, barely above a whisper, but in the end second-degree murder suspect Haydee Rivera-Nadeau pleaded guilty in Strafford Superior Court to killing her former girlfriend after she broke up a 12-year relationship and left her for another woman in the spring of 2023.
Rivera-Nadeau, dressed in olive drab jail garb, often seemed detached and aloof during the hourlong plea hearing, prompting Strafford Superior Court Judge Andrew B. Livernois to closely question her several times as to her cognition and awareness of what she was pleading to.
At one point when she simply nodded her head to one of Judge Livernois' questions, he reminded her she had to speak loud enough for the audio recording equipment used in the courtroom to memorialize testimony.
The capped plea she agreed to allows for a sentence of anywhere from 28 to 56 years for the 66-year-old Rivera-Nadeau, formerly of Old Rochester Road, Somersworth.

The plea allows to have three years suspended off the minimum sentence if she has no problems the first five years of her sentence, Asst. Attorney General R. Christopher Knowles told The Rochester Voice on Thursday following the hearing. Rivera-Nadeau also pleaded guilty to falsifying physical evidence for trying to conceal the murder weapon, a handgun she often carried with her, according to court testimony.
She also waived her right to appeal the judge's sentence, which will be handed down on Jan. 30.
Nadeau-Rivera was indicted in August 2023 on two counts of second degree murder, one count of falsifying physical evidence and one count of stalking.
The indictment alleged that on May 1, 2023, Rivera-Nadeau followed her longtime partner Lisa Rocheleau, 54, of Rochester, to her place of employment on Winter Street in Rochester, where she "aimed a firearm at Ms. Rocheleau's face ... and shot her."
According to a Rochester Police affidavit, Rivera-Nadeau told an acquaintance the day after the shooting that her former lover's death was an accident.
Rocheleau died at Portsmouth Regional Hospital a few days after she was shot after never regaining consciousness.
Rivera-Nadeau and Rocheleau had been in a longtime "toxic" relationship, according to a Gofundme page set up to help the Rocheleau family.
"Lisa was finally happy for once in her life, after working up the courage to leave (the relationship)," the Gofundme page stated.
A member of Rocheleau's family who discovered her on the floor of her title business inside the Winter Street Professional Arts building told police that Rivera-Nadeau "had a history of being verbally and physically violent," however no law enforcement agency had documentation of such.
A digital extraction of Rocheleau's phone revealed that Rivera-Nadeau had texted her regarding the possibility of her "cheating on her" within the week preceding the shooting.
On the day of the shooting an employee of the suspect's pest control business said she got a call from her boss around 7:45 a.m. during which she said, "I love you, I'm sorry, I'm going away, please take care of my dog," the affidavit states.
Surveillance video at the 40 Winter St. building shows that a person identified as Rivera-Nadeau arrived at 6:39 a.m. on May 1, 2023, and left the property at 7:16 a.m.
Police spoke with another acquaintance of the suspect on May 2, 2023, who said Rivera-Nadeau called her that day to tell her that the shooting was an accident, the affidavit states.
Also that, "she didn't mean to hurt anyone, that she just went to Lisa's office to drop off a plant" and "that they got into an argument."
According to the affidavit, "At some point she (Haydee) had the gun in her hand and it clicked. Lisa then got scared and went towards her (Haydee) and the gun accidentally went off and hit Lisa in the head."
Rivera-Nadeau then told the acquaintance she was on the run, because "the police won't believe it was an accident."
Rivera-Nadeau remains held at Strafford County Jail while awaiting sentencing.

Rocheleau leaves behind three sons.