Robert Dziekanski died in October 2007 after he was jolted several times with a Taser. (Paul Pritchard)

The RCMP's second-in-command said Monday the force is "very sorry" for the death of Robert Dziekanski, but he stopped short of admitting the Mounties made a mistake.

Dziekanski died after four RCMP officers used a Taser to subdue him at Vancouver International Airport in October 2007.

On Monday, Deputy Commissioner Bill Sweeney expressed regret for what happened, speaking at a Senate committee hearing in Ottawa.

"We are very sorry for Mr. Dziekanski's death and are committed to learning as much as possible from this terrible event," he said.

But Sweeney was very clear that until the Braidwood inquiry currently underway in Vancouver is completed, he won't comment on the specifics of what happened.

More de-escalation training needed

Sweeney did say situations involving police can escalate in a millisecond despite an officer's best intentions. He said the RCMP must spend more time training in de-escalation techniques.

"We always prided ourselves on time, talk and, if necessary, tear gas, before we'd have to do interventions that would cause harm to others," he said.

Walter Kostecky, the lawyer for Dziekanski's mother, said Sweeney's use of the word "sorry" is a good sign, but it isn't the first time he's heard it. Kostecky noted that Gary Bass, the RCMP's deputy commissioner for B.C., made similar apology a year and a half ago.

"It's got to go beyond that. I think it's got to be to the point where somebody accepts responsibility that these actions were not carried out in a way that's acceptable to the Canadian public," Kostecky said Monday after hearing the comments.

Expert defends officers' actions

While Sweeney was expressing his regrets to senators in Ottawa, an RCMP use-of-force expert testifying at the Braidwood inquiry in Vancouver gave what has become a familiar defence of the officers involved.

RCMP trainer Corp. Gregg Gillis said Monday that Mounties are trained to use Tasers, batons or pepper spray and to avoid physical fights with people to try to minimize the risk of injury to all parties.

Gillis said that the Mountie who stunned Dziekanski with a Taser acted in accordance with his training.

The Braidwood inquiry, which is looking into Dziekanski's death and might make findings of misconduct against individuals who were involved, resumes Tuesday with testimony from a psychologist, a psychiatrist and an epidemiologist.

With files from The Canadian Press