VANCOUVER -- The trial of an RCMP officer charged with perjury for his testimony at the public inquiry into the Robert Dziekanski case is hearing from witnesses who saw the Polish immigrant's fatal confrontation with police at Vancouver's airport.

The Crown alleges Const. Bill Bentley lied to the inquiry when he attempted to explain discrepancies between his initial accounts of what happened in October 2007 and an amateur video of the incident that emerged later.

In particular, Bentley initially claimed Dziekanski came at RCMP officers screaming before he was stunned with a Taser and then had to be wrestled to the floor -- both of which are contradicted by the video.

Greg Sambrook, who was on duty as airport operations manager that night, says his memories have faded with time and blurred after watching the video, but he was taken through various statements he gave to police.

The defence highlighted several instances in which Sambrook made the same sorts of errors that Bentley made, telling police Dziekanski was screaming and swinging a stapler before he was stunned and that he was physically taken down.

But in those same statements, the Crown notes that Sambrook also repeatedly said Dziekanski fell backwards to the ground after he was stunned with a Taser.