The half-brother of canal death accused Mohammad Shafia concluded his testimony Tuesday morning by saying the police failed to do their job properly in the murder investigation.

Dr. Mohammad Anwar Yaqubi told the Kingston, Ont., courtroom that his brother is not a murderer and the investigators should be on trial, not his family members.

Shafia, 59, his wife Tooba Yahya, 41, and their eldest son Hamed are charged with four counts of first-degree murder in the deaths of four of their family members in June 2009. They have all pleaded not guilty.

Zainab, 19, Sahar, 17 and Geeti Shafia, 13, as well as Shafia’s first wife in a polygamous marriage, Rona Amir, 50, were found dead in a submerged car in the Rideau Canal.

Shafia’s half-brother, a doctor living in the Netherlands, testified for the defence and described his early life with Shafia in Afghanistan and how the family fled to Pakistan when war broke out.

Court heard Tuesday that Amir told Yaqubi she wanted a divorce and she was looking for a $100,000 settlement.

He maintained however that his brother and his family members, who had been living in Montreal, were innocent.

The Crown alleges that divorce was part of the motive behind the killings. The prosecution's case also centres on the idea of family honour and allegations that the teenagers were killed because of their behaviour and boyfriends.

The trial, which started in October, entered its 37th day on Tuesday. During that time, jurors have heard from police, school officials, social service workers, the girls' boyfriends, and family members. Shafia and his wife both testified in their own defence.

Hamed Shafia's lawyer said his client will not take the stand.

Closing arguments in the case could start as early as Monday and the jury could begin deliberations by late next week.