The grieving mother of a man who died after being shocked with a stun gun at Vancouver airport last fall dabbed away tears Wednesday at a Commons committee studying the devices known as Tasers.

Sofia Cisowski told MPs in Ottawa that she wonders why RCMP officers didn't do more to help her son, Robert Dziekanski, after applying the device on him.

"Don't they have a responsibility to check on the man?" she said in a brief statement to the Commons public safety committee.

Tuesday would have been Robert's 41st birthday.

Walter Kosteckyj, Cisowski's lawyer, said she suffers post-traumatic stress following the ordeal that left her son dead.

Kosteckyj said Dziekanski was a lost soul whose fate was decided by a series of miscues amounting to "benign neglect."

Cisowski spent nine hours at the airport last October waiting in vain for her son who was immigrating from Poland to live with her in Kamloops.

The 40-year-old man spoke no English and became agitated after a series of communication breakdowns kept him in a secure part of the airport. When he finally emerged, his mother had already been told to go home because her son had not arrived.

RCMP were called after Dziekanski damaged a computer and threw a small table.

A video shot by another passenger shows the apparently co-operative man being Tasered and pinned to the floor by police. Minutes later, he was pronounced dead.

The incident set off an international uproar and helped spark several investigations into Taser use across Canada.

'Why aren't some alarm bells going off?'

Kosteckyj wondered what would have happened without the shocking amateur video of the incident, which was viewed by millions of Canadians.

"If we didn't have the tape, what would the police be telling us about this incident today?" he said.

Kosteckyj added he still can't understand how Dziekanski was left to wander the airport for hours.

"Why aren't some alarm bells going off? he said. "There's no one there to help that lost traveller."

Kosteckyj also criticized the way police put use of force ahead of tactful negotiation during their encounter with Dziekanski, suggesting good law enforcement is a lost art.

"It's knowing how to interact with people at the right time."

Police recently completed a homicide investigation into Dziekanski's death, but there is no word on whether charges will be laid.

Canada Border Services Agency officials say there were several attempts to help Dziekanski.

They point out he was given several glasses of water. His luggage was retrieved for him and staff helped find his documents.

Numerous attempts were made to contact his family. And once his family reached staff by phone, there was an effort to locate him.

In November, the Border Services Agency announced several steps including a review of services to international travellers and installation of more cameras in the agency's area of the Vancouver airport.

There is also consideration being given to additional patrols and security checks and changes to ensure people report for secondary examination within a reasonable time.