The jurors in the Shafia murder trial have received their final instructions from the judge and have begun their deliberations.

The judge delivered a 240-page address to the seven-woman, five-man jury, explaining that they could find the three defendants guilty of first-degree murder, second-degree murder, or not guilty.

"This is an important point because throughout the trial the Crown has argued that this was a planned and deliberate murder... about this being an honour killing," said CTV's Genevieve Beauchemin from outside the courthouse mid-day Friday.

Verdicts of second-degree murder, however, would not require "the same degree of premeditation," she added.

The jury saw 58 witnesses and a mountain of evidence during the trial.

Mohammad Shafia, 58, his wife Tooba Yahya, 42, and their son Hamed, 21, hare accused of murdering three Shafia daughters and Shafia's first wife from a polygamous marriage.

The bodies of the four were found June 30, 2009, in a car at the bottom of a canal in Kingston, where the Montreal family had stopped on its way back from a trip to Niagara Falls, Ont.

The Crown alleges it was a premeditated murder staged to look like an accident, something the defence used as its main argument during the trial.

Crown attorney Laurie Lacelle told jurors in her closing arguments the evidence against the three is irrefutable, particularly the wiretap evidence against Mohammad Shafia.

"She used a colourful analogy in a sense," Beauchemin told Canada AM Friday.

"She said that these three accused thought that there was a diseased limb on the Shafia family tree and that they had to prune the tree back to the good wood," Beauchemin said.

Lacelle described son Hamed as a "controlling brother" whose job it was to do surveillance on the sisters and report back if they did anything that went against the family honour code, Beauchemin said.

The mother, Tooba, was cruel to the first wife and there was evidence she had beaten her at times. The Crown alleged "that this mother chose not to protect her daughters," Beauchemin reported.

The father, Lacelle said, believed his daughters to be "treacherous" and "whores" and this is why they were killed.

Part of the defence's argument was that there was no way to prove how and where the four died.

But Lacelle said that wasn't a significant hole in the prosecution's case.

The end of closing arguments was delayed Thursday for several hours after a bomb threat evacuated the courthouse where the trial is being held.

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