Police suspected close to a third of people they Tasered were suffering from mental illness and more than half were affected by alcohol or drugs at the time, an Ombudsman's inquiry has found.
In three-quarters of cases, a Taser was used on a person not carrying a weapon.
The NSW Ombudsman today released findings of a detailed analysis of NSW Police Taser use in 556 cases from June 1 to November 30, 2010.
Died during arrest ... Roberto Laudisio Curti.
Of those incidents, the Ombudsman found 27 cases of inappropriate use in which a Taser was fired. There were an additional 53 cases of inappropriate use where a police officer armed but did not fire a Taser.
The Ombudsman, Bruce Barbour, said while his report identified only a small number of incidents a Taser was misused, "it is unacceptable to see situations where Taser use failed to comply with police procedures and was unreasonable".
Mr Barbour said his investigation showed procedures for Taser use were unclear, confusing or absent in some important areas.
"The rules need to be clearer and stronger," he said. "In my view, police must be at risk of serious actual bodily harm to justify discharging a Taser.
"Clear and unambiguous guidance on appropriate and inappropriate Taser use benefits the community, as well as police officers.
"Police must be certain that when they use their Tasers they are doing so lawfully and in line with procedure."
The report found that Tasers were used against a male in 89 per cent of cases. In more than half of cases, the male was affected by alcohol and/or drugs.
The people who were Tasered did not have a weapon in 74 per cent of incidents.
In 31 per cent of incidents which were examined individually, police suspected the subjects of Taser use were suffering from mental illness.
The Ombudsman made 46 recommendations.
These included never applying a Taser to one person for more than 15 seconds in total, and never using a Taser to force compliance. Officers should be in danger of serious bodily harm before they discharge one.
Police Commissioner Andrew Scipione defended the use of Tasers by police, saying the devices were appropriate in most cases.
He said police had used them in incidents where people had threatened to harm themselves.
Police Minister Mike Gallacher said police would respond to the 46 recommendations made by the Ombudsman's report, "How are Taser weapons used by the NSW Police Force?"
The police response would include consideration of the recommendations from a coronial inquiry, expected on November 14, into the death of Brazilian man Roberto Laudisio Curti.
Mr Gallacher said he would continue to support the use of Tasers in the NSW Police Force and said they were effective as a "de-escalator" of violence.
NSW Greens MP David Shoebridge said it was "remarkable" that the Ombudsman has released his Taser review without considering the "disturbing evidence and compelling submissions" from the Roberto Curti coronial inquiry.
"The highest-profile potential abuse of Tasers by NSW Police has flown under the Ombudsman's radar and failed to inform this report," he said.
"One of the clear options for limiting Taser use by police is to withdraw them from general duties officers and limit them to specially trained squads.
"This was the recommendation of the Ombudsman in his last review but, despite the ongoing abuses of the weapon, has not been supported in this review.
"This report raises serious ongoing concerns with the police use of Tasers but proposes little other than tinkering with the existing regulations."
Mr Barbour said he could not discuss the Curti matter while it was before the coroner who has been given a copy of his report.
He rejected the criticisms from Mr Shoebridge as unfair.
"This report deals with over 2000 incidents up to November 2011," Mr Barbour said.
"The very tragic death of Mr Curti took place in March this year and was not considered as part of the review.
"Independent to this review we are oversighting the police critical incident investigation of that matter and it would be inappropriate and improper for me to put forward any views until such time as the coroner has completed her inquest and has handed down her findings."
Mr Curti's family released a statement in response to the Ombudsman's report.
"The family of Roberto Laudisio Curti notes the report released by the NSW Ombudsman today in relation to Taser usage.
"The family believes that many of the recommendations relate to the way in which Taser was used on the night Roberto died, including multiple uses of Taser (particularly in "drive stun" mode), use on a person who is fleeing, and use on a person after he or she is handcuffed. The family feels that several of the Ombudsman's recommendations are a step in the right direction.
"However, we do not wish to comment on any specific matters which may be relevant to the Coroner's findings regarding the death of our beloved Roberto.
"As outlined in Mr Hamill's closing submissions last Friday, we strongly believe that individual accountability relating to the misuse of Taser is essential. Without it, any policies, guidelines and training are likely to be significantly less effective."