Major doubts emerged today over Government plans to issue police with 10,000 new Taser stun guns.
The country's largest force will not be taking up funding for the 50,000-volt weapons because they could "damage public confidence", a police authority spokesman said.
Human rights group Amnesty International said Tasers were "potentially lethal" and had been linked to hundreds of deaths in the US and Canada.
And it emerged a senior cabinet minister expressed reservations about extending the use of Tasers when working at the Home Office.
Communities and Local Government Secretary Hazel Blears said she would not want to see the guns issued to every officer and rejected the idea of their use as an "everyday weapon" when she worked at the Home Office.
"(The) Taser is quite a dangerous weapon. It is a less lethal option other than firearms, but it is not an everyday weapon used in everyday circumstances," she told Police Review in 2005.
"My feeling at the moment is that it is substantially different from handcuffs and a truncheon, and I would not want to see everyone on the streets having that kind of weapon."
Until recently, Tasers could be used only by specialist firearms officers.
But a year-long Home Office pilot extended their availability to other officers given new training in 10 forces.
Ministers said the trial revealed the threat of Taser use was often enough to stop a violent incident.
Tasers were deployed on more than 600 occasions in the past year but only had to be fired 93 times, ministers said.
Today's funding extends the availability of Tasers to all 43 forces in England and Wales.
The use of the weapons will be restricted to incidents in which officers or members of the public face the threat of serious violence.
But Oliver Sprague, Amnesty International's UK's arms programme director, said the use of the guns should be restricted to "life threatening" or "very dangerous" situations.
He said: "Amnesty recognises the very difficult job police officers have to do and we don't actually oppose the use of Tasers as long as it's by a limited number of highly-trained specialist officers, responding to genuinely life-threatening or very dangerous situations.
"Tasers are potentially lethal weapons which are already linked to numerous deaths in North America and that's why wide deployment without adequate training is a dangerous step too far for British policing.
A report released today by the Independent Police Complaints Commission found 35 complaints had been made against police using Tasers since they were first introduced in September 2004.
Of the 15 most serious investigated by the IPCC, the majority were about Tasers used in "drive-stun" mode, where the gun is held directly against the body.
The shock was applied directly to the head, chest, neck and shoulder blades of suspects, the report found.
Police guidance suggests Tasers should not be used in drive-stun mode against the head or neck unless "absolutely necessary" to save lives because of the "increased risk" of injury, the report said.
The police watchdog received a complaint from a man who claimed he had suffered amnesia after being hit by a Taser.
Other suspects went to hospital to have barbs removed from their skin - one from his back and another his thumb.
Home Secretary Jacqui Smith said: "I am proud that we have one of the few police services around the world that do not regularly carry firearms and I want to keep it that way.
"But every day the police put themselves in danger to protect us, the public. They deserve our support, so I want to give the police the tools they tell me they need to confront dangerous people."
The move was welcomed by the Association of Chief Police Officers (Acpo), which said trials showed in the majority of cases Tasers helped police resolve incidents without resorting to other weapons.
Derek Talbot, Acpo spokesman on Tasers said: "This reinforces the value of Taser as a useful tool to make the public and officers safer and to resolve potentially violent situations effectively and rapidly.
"The conclusions of this trial provide further evidence that Taser is a proportionate, low risk means of resolving incidents where the public or officers face severe violence or the threat of such violence which cannot safely be dealt with by other means," he said.
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