Dr Bruce Cohen at the Department of Sociology, University of Auckland, suggests that Tasers might work - as long as they're not used.

There may yet be evidence that Tasers work. A recent report from the Vancouver police explained that "subjects appear to comply more often when they are confronted or challenged with a Taser", rather than when the Taser is actually discharged.

Criminologists call this "the Velcro effect": police merely have to unfasten the weapon to achieve compliance.

If the Taser is actually discharged the problems begin, or - as in the case of the two recent police incidences with armed offenders in West Auckland and Christchurch - nothing happens.

Despite reassurances from New Zealand police chiefs that the Taser continues to be safe and effective, I would argue that this is a limited and naive view of a weapon that not only misfires but can cause injury and sometimes death.

The use of Tasers should be of serious concern not only to officers in the field but to all of us.

Since the late 1980s, Taser use in policing has grown dramatically and it is used by more than 14,000 law enforcement agencies in more than 40 countries.

Following a review of "less lethal weapons" as an alternative to arming the police with guns, Tasers were introduced by the New Zealand police in August 2008.

The case of Senior Constable Keith Abbott, who fatally shot Steven Wallace in Waitara in 2000, was the precursor to the New Zealand police review.

It was theorised that Wallace's life could have been saved if Tasers had been available. Unfortunately there is little evidence to suggest Tasers are generally used in this manner in the field.

The incidences in West Auckland and Christchurch are atypical, and in both cases the officers still resorted to shooting the offender. Following the Taser failures, the New Zealand Police Association president Greg O'Connor stated that Tasers were not actually designed to be used against armed offenders.

It was admittance on the part of the New Zealand police that Tasers were never considered to be a non-lethal alternative.

In the United States, where officers routinely carry guns, the evidence suggests that officer shootings of offenders have not declined since the introduction of Tasers.

At the University of Auckland we have been surveying the introduction of Tasers in New Zealand, the United States, and Britain. There are some startling contradictions between the justifications and the use of Tasers in the field.

Whereas police and policymakers argue the technology is a necessary alternative to lethal force, the majority of Taser use is carried out in low-risk situations and against specific populations who are most susceptible to health risks from being Tasered (for instance, alcohol and drug users as well as those with mental health problems).

Amnesty International has gone so far as to claim that 334 deaths in the United States can be attributed to police use of Tasers. The available evidence further suggests that minorities are over-represented in these figures (of those Tasered during the 2006-07 trial period in New Zealand, 29 per cent were Maori and 27 per cent were Pacific).

One further caveat is worthy of note here. Although it is too early to fully evaluate the effect of the introduction of the Taser on violent crime rates or officer assaults in New Zealand, we have found no clear evidence of downward trends in the United States or Britain on either indicator. This further challenges the justifications for introducing such technology to the police.

But what of "the Velcro effect"?

In a similar analysis of police use of force, Dr John Buttle at Auckland University of Technology suggests such threats are as likely to be neutralised by other signals of police authority such as the police baton, the police uniform, or simply by an officer shouting stop.

He concludes that what really makes the difference is "the actions of the police officers rather than the characteristics ascribed to any single weapon".

So while the focus of the debate in New Zealand has centred on different weapons to use in the field (in this case, Taser versus gun), this is a red herring.

Rather, a refocusing of the debate around the broader issues of police action and behaviour in our communities would seem to make more sense.