Kyle Edmund Scott of the Woodstock area has admitted to killing 82-year-old Sarah Kennedy in her Richmond Corner home on Oct. 5.
Scott, 20, changed his plea to guilty of second-degree murder on Tuesday in a court appearance at the Court of Queen's Bench in Woodstock.
A statement of facts agreed upon by the Crown and defence was read to Justice Terrence Morrison and stated Scott had no connection to Kennedy.
Scott, who was 19 at the time of the killing, was driving on his all-terrain vehicle in the area and it broke down, leading him to knock on Kennedy's door and ask to borrow a pair of pliers to try and fix the ATV.
When Scott couldn't fix the ATV, he asked Kennedy to drive him to his brother's house. Kennedy did, but Scott's brother was not home, so they both returned to Kennedy's home.
The statement says Scott then went to use the bathroom and could hear voices in his head and began hitting his head to get rid of them.
Upon leaving the bathroom, Scott picked up a hammer and hit Kennedy in the head numerous times with it. He then removed her clothing to make it look like a sexual assault and slit her throat with a kitchen knife.
Scott then cleaned himself up, returned the hammer to where he found it, and stole Kennedy's purse as he was leaving.
The court heard he took Kennedy's car and attempted to leave the province.
He attempted to go to Prince Edward Island and got as far as the Confederation Bridge before turning around for some reason.
The statement also indicates Scott went to St. Stephen and bought hair dye.
Scott's sister then telephoned him and told him to turn himself in.
Scott then drove to his sister's home in Maugerville and spent the night there.
Meanwhile, one of Kennedy's neighbours called a member of the 82-year-old woman's family when it was noticed Kennedy's television had been on for days.
When a family member went to check on Kennedy, her body was discovered. It was then noticed that Kennedy's car was missing and an all-points bulletin was issued by the RCMP.
The statement of facts said the car was found outside of Harvey, with Scott driving. His sneakers were spattered with blood that proved to be Kennedy's from DNA analysis.
Scott underwent a 30-day assessment at the Restigouche Hospital Centre for psychiatric care in Campbellton last fall and was deemed fit to stand trial.
The report found he "did not suffer from mental disorders so as to exclude him from criminal responsibility."
Scott kept his head down in court throughout Tuesday's proceedings.
The judge repeatedly asked Scott if he was sure he wanted to plead guilty and reminded him that such a plea carried an automatic life sentence in prison with no chance of parole for at least 10 years.
Scott's family members in the courtroom became emotional when the judge was talking about a life sentence in prison.
A sentencing hearing regarding Scott's parole eligibility is scheduled for May 29.