RCMP Const. Kwesi Millington spoke publicly Monday for the first time about events that led to Robert Dziekanski's death. (CBC)

After Robert Dziekanski fell to the floor, screaming and in pain from the first jolt of a Taser, the officer who deployed the stun gun shocked him a few more times because he thought Dziekanski was combative and resistant, a public inquiry heard Monday.

RCMP Const. Kwesi Millington, 32, told the Vancouver inquiry into the Polish immigrant's death that he delivered the first shock from the 50,000-volt weapon because Dziekanski had picked up a stapler and become a threat.

"I formed the impression that he wanted to attack one of the officers or all of the officers," said Millington in his first public account of the events leading up to Dziekanski's death at the Vancouver airport in 2007.

Millington said he fired the Taser again even after Dziekanski was lying on the floor because the first jolt did not immobilize him. In all, he fired the stun gun four times, although the records indicate the Taser was discharged five times, the inquiry heard.

"The person that it's applied against is supposed to fall immediately and it's supposed to immobilize them," Millington said. "It did not have that effect so I felt it was necessary to fire it again."

'He was in a combative stance as we called it and was approaching the officers, I believe, with the intent to attack, so I deployed the Taser at that point.'— RCMP Const. Kwesi Millington

Millington said Dziekanski was still struggling, although when the second stun began, he was already on the floor and the other officers hadn't yet approached to restrain him.

"Can you tell us how four healthy members of the RCMP could not gain control over him when he's in that position, right there lying on the ground, making the noises he was making?" asked Art Vertlieb, the inquiry's chief counsel.

"He was still fighting and struggling with us," Millington replied.

Dziekanski was immigrating to Canada from Poland and spoke little English. He died on Oct. 14, 2007, shortly after being stunned by Mounties up to five times. He had been wandering the Vancouver International Airport for hours and became agitated after a series of communication breakdowns kept him in a controlled area.

Millington testified Monday that Dziekanski was sweaty, wide-eyed and anxious when the RCMP first encountered him during the early morning hours at the international arrivals lounge.

Robert Dziekanski was jolted up to five times with a Taser by RCMP officers at the international arrivals area of Vancouver International Airport. (Paul Pritchard)

After trying to use hand signs in an attempt to calm him down and verbally asking for Dziekanski's passport, Millington said Dziekanski turned away toward a desk, a move Millington said he interpreted as defiant.

Instead of complying with the officer's commands, Dziekanski, who did not speak English, picked up a stapler and started to approach the other officers, Millington testified.

"He had the stapler open, the other fist raised. He was in a combative stance as we called it and was approaching the officers, I believe, with the intent to attack, so I deployed the Taser at that point," he said.

The officer said he used the stun gun three more times because Dziekanski continued to resist the officers, but he said in some of those instances, the Taser probes may not have made proper contact with Dziekanski's body and no shock was administered.

After Dziekanski was on the floor, Millington said he used the Taser to get what he called "pain compliance" from Dziekanski to allow fellow officers to handcuff him.

He said his superior officer ordered him to use the Taser a third time, so Millington used the device again, but it made a "clacking" noise and he believed it didn't have any effect on Dziekanski.

He said the other officers were still struggling to get Dziekanski's hands behind his back, so he switched the device to "push-stun mode," where the Taser is held against a person's body, and stunned him again.

Notes and video hold different accounts

Under questioning, Millington was unable to explain why the details in his official report on the incident differed from a video recording of the incident made by a bystander.

Millington's account of the number of times he used the stun gun contradicted expert evidence based on data collected from the Taser itself that showed the weapon had been used five times, not four, a discrepancy Millington was unable to explain.

Millington was also asked by Vertlieb about his police notes and incident reports, which were written shortly after the incident.

In those notes, Millington wrote that a combative Dziekanski did not fall down until he was stunned three times with the Taser and officers wrestled him to the floor.

But when the video recording captured by bystander Paul Pritchard at the airport was played at the inquiry, it showed Dziekanski fell on his own shortly after the first Taser jolt.

Millington admitted his notes and incident report were wrong. When asked to explain the discrepancies, he said, "That's what my notes said. He fell on his own. I did not realize that."

Millington is the third officer to testify at the inquiry, and although the Crown has ruled criminal charges will not be laid against any of the officers involved, the inquiry commissioner could make findings of misconduct.

With files from the Canadian Press