HALIFAX -- Three judges with the Nova Scotia Court of Appeal have reserved their decision on William Sandeson's appeal of his conviction for the murder of a fellow Dalhousie University student in 2015.

A two-day court hearing wrapped up Tuesday with a Crown lawyer insisting police and prosecutors acted properly during Sandeson's trial for the first-degree murder of Taylor Samson.

Samson was last seen alive in August 2015 on video surveillance, walking into Sandeson's south-end Halifax apartment.

His remains have never been found.

On Monday, lawyer Ian Smith argued Sandeson should be granted a new trial, partly because his defence team was allegedly "betrayed" by a private investigator they had hired.

Smith alleged that Bruce Webb turned out to be a "traitor" when he secretly told police about key aspects of the case.

Crown lawyer Jennifer MacLellan challenged that view, saying Webb's actions had little impact on the trial. However, Justice David Farrar said at one point he couldn't imagine how Webb's actions could be seen as anything but a breach of litigation privilege.

Sandeson was sentenced in July 2017 to life in prison for fatally shooting Samson during a drug deal in August 2015. Smith argued the verdict was unreasonable, and that police acted improperly during a lengthy interrogation and when they searched Sandeson's apartment without a warrant.

Another area Sandeson's lawyer spent a lot of time focusing on was the search of his apartment.

They said police entered without a warrant 68 hours after Samson was last seen.

Tuesday, the Crown argued police had reasonable grounds to enter Sandeson's apartment because they believed Samson may have been held hostage as part of a drug rip.

"My friend said yesterday somehow that the passage of time made the circumstances less exigent here," MacLellan said. "That because this wasn't, I guess, a couple of hours after Taylor (Samson) had gone missing, that somehow it was less exigent to find him and I don't see how that holds up."

The other two grounds for the appeal stem from the interrogation of Sandeson after he was initially arrested by police for kidnapping and whether the first-degree murder conviction was unreasonable.

This report by The Canadian Press was first published Jan. 21, 2020.

With files from CTV Atlantic's Natasha Pace.