Christopher Husbands was convicted of two counts of second-degree murder in December, after he shot Ahmed Hassan and Nixon Nirmalendran in the food court of the Toronto mall two years before.
Hassan died at the scene, while Nirmalendran succumbed to his injuries in hospital days after the shooting on June 2, 2012. Other people in the mall were wounded by the shots Husbands fired, but survived the shooting.
In December, Husbands was also convicted of five counts of aggravated assault, one count of criminal negligence causing bodily harm and one count of reckless discharge of a firearm.
The Crown is asking for Husbands to serve a sentence of 40 years before he is able to apply for parole.
Dirk Derstine, who is representing Husbands, had challenged this possibility. But the judge rejected that challenge on Thursday.
The judge said he will not give Husbands a sentence longer than what the Crown is asking for.