The death in Pitt St has again triggered demands by civil rights groups for a rethink of the use, and even definition, of non-lethal weapons by the nation's police forces.
Tasers fire darts trailing wires and deliver an electrical shock that immobilises by causing skeletal muscle spasms. Pepper spray uses capsicum-derived compounds to cause temporary blindness.
Both are employed as an alternative to firearms to avoid lethal force, and are considered an essential tool to reduce risk to both police and suspects, even by organisations critical of their widespread use and potential for misuse.
Each has caused or contributed to deaths, but while comparatively little research has been conducted in Australia since Tasers were introduced in the mid-1990s, international experts say the incidence of deaths is low.
British expert Anthony Bleetman told ABC radio yesterday: "What I would say is that if you looked at Taser in isolation as a use of force option, I believe it's been used approximately four million times since the device was deployed, and when Taser alone was used there have been a small number of deaths which represent a very, very, very small percentage of fatalities in relation to Taser use."
Of more than 250 Taser-related fatalities reported in the United States, in only a handful was the impact of the Taser confirmed to have been the prime cause of death.
Bleetman warned against jumping to conclusions over the Pitt St death.
"I think it is very presumptuous for anyone to determine the cause of death is a Taser simply because it's occurred in an incident where a Taser has been utilised."
Six people have now died after being Tasered in Australia - one after being shocked 28 times - and others have been injured, including two men seriously burned when Tasers were used near inflammable goods.
There is also concern that Tasers are increasingly being used as an easy option.
While rules have been tightened, studies across Australia have warned of "usage creep", in which Tasers are fired outside guidelines.
A report by Victoria's Federation of Community Legal Centres, supported by similar papers in other states, said that real risks of Taser-related death or serious injury faced vulnerable groups such as people with mental illness, pre-existing health issues, or who were drug and alcohol affected.
Between 2004 and 2009, 85 per cent of Taser use by Victorian critical incident response teams was against people with mental illness, 28 per cent against unarmed suspects, and almost one-third to force people to comply with instructions.
The West Australian Crime and Corruption Commission found a fourfold increase in the use of Tasers to threaten people between 2007 and 2009, and their use against indigenous suspects doubled to 30 per cent.
Concern has also been raised at the risks of increasing use of pepper spray, especially in combination with Tasers.
"As far as I'm aware there have not been any published studies describing the combined use of pepper spray and Taser, and that's perhaps something that should be looked at by looking at use-of-force reports from around the world," Bleetman said.
At least three men are known to have died after being pepper-sprayed in Australia, including one who had also been Tasered.
Studies in the US and Canada have shown that only small numbers of people had died after being pepper-sprayed, and all cases involved other factors such as asthma or drug use.
Yesterday the New South Wales Council for Civil Liberties called for an immediate moratorium on the use of Tasers following the Pitt St death, and said there was a danger that police were drawing their Tasers simply because people did not comply with directions.
Greens police spokesman David Shoebridge called for an urgent independent inquiry, saying Taser use had risen while the use of guns by police had not fallen.
NSW Premier Barry O'Farrell said he was concerned at the death but said he supported Tasers as an alternative to firearms.
- Greg Ansley
FATAL SHOCK
* A man, believed to be South American, dies after being Tasered and hit with capsicum spray on Pitt St in Sydney. Police allege he resisted arrest by officers investigating an incident in a convenience store.
November, 2011: A man dies on the railway tracks at Sydney's Central Station after stabbing himself in the neck and then being Tasered by police.
October, 2010: A man dies after police Taser him in the chest outside a home in Sefton in western Sydney. He was allegedly armed with two knives.
June, 2009: Antonio Galeano, 39, dies after being shocked multiple times by police during a disturbance at his girlfriend's house in Brandon, a town in the north of Queensland.
April, 2009: An Alice Springs man, 39, dies in custody after being hit with capsicum spray and a Taser. Police used the weapon to restrain him when they attended a domestic dispute.
May, 2002: New South Wales man Gary Pearce, 56, dies of a heart attack about two weeks after being jolted with a stun gun while threatening police with a frying pan. Mr Pearce had heart disease, hepatitis C and schizophrenia.
- AAP
