A day after the Ontario government moved to expand the use of stun guns to front-line police officers, a man who studied their use in the RCMP says the weapons are often misused.

Paul Kennedy, former chair of the commission for public complaints against the RCMP, investigated the use of stun guns after the death of Robert Dziekanski, who was hit multiple times with a stun gun at Vancouver's airport in 2007.

Kennedy said stun guns are an effective tool that police should have, but that they often are used too quickly by officers involved in confrontations.  

In an interview on CBC Radio's Metro Morning on Wednesday, Kennedy said police should use Tasers only when there is an imminent threat to officers or to the person they are trying to arrest.

Often, however, Kennedy said officers reach for their stun gun the moment a confrontation begins.

"It becomes used right after talking and sometimes before talking," he told host Matt Galloway.

"Instead of the device being used as the last tool of resort prior to shooting somebody, it became almost the first tool of resort following a confrontation with an individual."

Kennedy said his research uncovered cases in which stun guns were used on children as young as 13, on people in their 80s, and on suspects already handcuffed and surrounded by police officers.

Ontario move follows Sammy Yatim death

The Ontario government’s move allows individual police forces to decide which officers are issued stun guns. Prior to Tuesday's announcement, Ontario had restricted the use of stun guns to supervising and tactical officers, setting Ontario police apart from counterparts in several other provinces and with the RCMP.

The announcement came exactly one month after the death of Sammy Yatim, the 18-year-old fatally shot aboard a Toronto streetcar last month during a confrontation with police. Officers used a stun gun on Yatim after he had been shot multiple times. Toronto police Const. James Forcillo Toronto is facing second-degree murder charges in his death.

Ontario Community Safety Minister Madeleine Meilleu said Tuesday’s announcement had been in the works for months and was not related to the Yatim shooting. She added that expanding stun gun use will result in fewer deaths, and their use will be closely documented and monitored.

Kennedy said officers have to understand that stun guns cause "intense pain" and have the potential to cause death. Expanding their use to more officers brings new risks, he said.

"It’s a weapon and it has to be used in the right circumstances and it can’t be misused," he added. "Otherwise you’re just going to have examples of what I call casual cruelty, and that’s a real risk."