But amid the gruesome details of the 26-year-old's death in February 2014, the motive for the slaying remains a mystery.
Blake Leggette and Victoria Henneberry were both charged with first-degree murder last year and they both pleaded not guilty at the time. As their trial was starting Wednesday, Leggette changed his plea to guilty and Henneberry pleaded guilty to a lesser charge of second-degree murder.
Two statements of fact submitted to Nova Scotia Supreme Court say the couple was having "financial difficulties" soon after they moved into a sublet room in Saunders' apartment, which they had found through a Kijiji ad in January 2014.
The documents say the two wanted to get out of Halifax, but they don't say why.
"Mr. Leggette planned to kill Ms. Saunders, take her car and leave the province," both statements say.
On Feb. 13, 2014, Saunders went to collect rent from the couple but they didn't have the money, and Henneberry lied when she said she had lost her bank card and needed to contact her bank, according to the statement.
Leggette then grabbed Saunders by the throat and choked her, but the young woman fought back, managing to tear through the three plastic bags he pulled over her head.
At one point, Leggette and Saunders fell down. He twice hit her head on the floor and she stopped moving.
"Ms. Henneberry remained during the struggle," the documents say.
Saunders body was found in a hockey bag on the side of the Trans-Canada Highway near Salisbury, N.B., about two weeks after she was last seen on Feb. 13, 2014.
Leggette and Henneberry were arrested five days later in Harrow, Ont., while driving Saunders' car. They also had the young woman's phone, bank card and identification.
At a four-day preliminary hearing held last summer, the court was shown a video recorded by Leggette on Feb. 8, 2014, showing he and Henneberry arguing as they appear to discuss killing Saunders.
No context was provided for the video, but in it Leggette tells Henneberry: "You think this is all gonna get blamed on me?"
Later, she tells Leggette: "You said you wanted to kill Loretta."
He asks her where he said that, and Henneberry replies: "Stop lying."
Leggette will be sentenced to an automatic life sentence with no parole eligibility for 25 years. Henneberry is also facing a life sentence, but her parole eligibility could range between 10 and 25 years.
Saunders was an Inuit student at Saint Mary's University, where she focused her studies on missing and murdered aboriginal women.
As the guilty pleas for Leggette and Henneberry were entered into the court record Wednesday, the courtroom remained silent. Several members of Saunders' family, including the victim's mother, sat stone-faced throughout the proceedings.
Outside court, Leggette's lawyer said his client is remorseful for what happened.
"I'm sure he's very relieved in that it's over and done with and that he has publicly accepted responsibility, but he's very concerned as well," said Terry Sheppard.
"He did not want to have the Saunders family go through the very gruelling process of a public trial with all of that evidence coming out."
A sentencing hearing has been scheduled for next Wednesday, when victim impact statements are expected to be delivered. Judge Josh Arnold will also decide on Henneberry's parole eligibility period.
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