Crown prosecutors began framing the deaths of three teenage girls and their father's first wife as an "honour killing" in an Ontario courtroom on Thursday, more than two years after the victims were found submerged in the Rideau Canal near Kingston, Ont.

It's expected that the honour killing narrative will be key to the prosecution's case against the accused family members: Tooba Mohammad Yahya, 41, husband Mohammad Shafia, 58, and son, Hamed Mohammad Shafia.

All three face four counts each of first-degree murder, and all three have pleaded not guilty to those charges.

On June 30, 2009, 19-year-old Zainab Shafia, 17-year-old Sahar Shafia, 13-year-old Geeti Shafia and 50-year-old Rona Amir Mohammad were found dead inside a dark Nissan that had fallen into a canal lock.

While the family said that the deaths were the result of a joyride gone wrong, police had different suspicions, court heard.

Only days later, the girl's father was secretly recorded by police talking about the deaths and linking them to honour, prosecutors said.

Other conversations, secretly recorded by police, reveal that the girls' father felt betrayed because his daughters had boyfriends, Crown attorney Laurie Lacelle said.

"Even if they hoist me up onto the gallows, nothing is more dear to me than my honour," Shafia said, according to Lacelle. "Let's leave our destiny to God, and may God never make me, you or your mother honourless ...There is nothing more valuable than our honour."

The recordings were made in the aftermath of the deaths when police began to suspect that family members may have been involved.

Officers bugged the family's vehicle, and in order to spur conversation, police then told the Shafias that they had found a camera near the scene of the deaths, and that it was being examined.

The Shafias, however, scoffed at the police, and said that they were bluffing.

"If they had had any proof they would have come for us a long time ago," Shafia said.

A separate wire recorded Shafia and Yahya, his second wife, talking about their daughters three weeks after the deaths.

"If we remain alive ... we have no tension thinking our daughter is in the arms of this or that boy, this or that man," Shafia said.

"God's curse on them for generations. May the devil (defecate) on their graves. Is that what a daughter should be? Would a daughter be such a whore?"

Lacelle continued to quote Shafia: "There can be no treachery, no violation more than this … They committed treason from beginning to end. They betrayed humankind. They betrayed Islam...They betrayed everything."

Along with the tape recorded statements, Lacelle told the jury that she would be calling expert witnesses and presenting evidence on honour killings. In some extreme cases, Lacelle said, killing is used to restore a family's honour.

The Shafia family lived in Montreal before the killings, but originally hail from Afghanistan.

Before the bodies of the three daughters and Mohammad, who was Shafia's first wife, the family was under stress, court heard.

Their eldest daughter, Zainab, had run away from the family, only to be coaxed home because her mother said she could marry her boyfriend.

But when the groom's family didn't come to the wedding, Zainab was forced to annul the marriage by her parents, court heard.

Sahar, 17, was also seeing a boy and the parents suspected that Geeti, 13, was also getting into a relationship, Lacelle said.

Plus, court heard that the two elder daughters were resisting their father by not wearing the hijab. Geeti, meanwhile, was caught stealing from a store and wasn't doing well in school, Lacelle said.

Court heard that Rona Amir Mohammad was Shafia's first wife, but when it became apparent that she could not bear children, Shafia married Yahya, Lacelle said.

Still, Rona Amir helped bring up the children and loved them like a mother, Lacelle said.

However, she was treated poorly and was beaten by Shafia, according to diary excerpts read in court by Lacelle.