HALIFAX - The husband of an elementary school teacher has admitted strangling his wife to death more than five years ago, closing a case that was kept in the public spotlight by a high-profile campaign led by her sisters.

Jason MacRae, 37, pleaded guilty to second-degree murder Wednesday after an extensive investigation by police in Halifax into the slaying of Paula Gallant.

Investigators had struggled to find clues in the 36-year-old woman's death until they announced in August they had charged her husband with first-degree murder.

Anyone convicted of second-degree murder must serve at least 10 years in prison before being eligible for parole.

Police say Gallant died on Dec. 27, 2005, and her body was found the next day. The Nova Scotia Supreme Court heard the cause of death was asphyxiation due to strangulation.

In an agreed statement of facts, court heard MacRae told undercover police officers that he got into an argument with his wife over debt on a Visa card.

It says Gallant was working at a computer in the couple's basement when MacRae hit her in the head with a two-by-four. A struggle ensued in the laundry room and MacRae told the officers he strangled Gallant with his hands.

Gallant is quoted in the statement as saying: "What are you doing? Stop."

The statement also says that MacRae admitted to undercover officers that the thought of killing Gallant had crossed his mind before.

"Honestly I thought about it before, but I didn't think I would ever do it," he is quoted as saying. "It just happened."

Halifax Regional Police Chief Frank Beazley said at the time of MacRae's arrest that key information was brought to the attention of investigators in the spring of 2009. MacRae was described by Beazley as a suspect early in the investigation.

Gallant's body was found in the trunk of her car outside Beechville-Lakeside-Timberlea Elementary School, where she had taught since 1999. She was a Grade 3 teacher.

The married mother of one had left home to go shopping earlier in the day. At the time of her death, she and MacRae had a one-year-old daughter.

A campaign spearheaded by Gallant's sisters, Lynn Gallant-Blackburn and Lana Kenny, kept public attention on the case.

After Gallant's death, the sisters started a letter-writing campaign to newspapers, hoping to rekindle dormant memories as the police investigation appeared to stall. The family also pushed the Nova Scotia Justice Department to increase the reward for information leading to an arrest and spoke out publicly about violence against women.

In a victim impact statement, Gallant-Blackburn spoke of the pain her family has suffered and the betrayal they felt after tending to MacRae's emotional needs.

She said the family wondered about the lack of emotion he showed at the time of Gallant's funeral and his reluctance to stand by his wife's casket at the funeral home.

"He had all the answers and could have ended the suffering. But instead he moved on without any regard for anyone but himself," she said.

"I have to live every day without my sweet baby sister in my life."