Three police officers have been injured while testing the controversial new taser guns, and now police are admitting there is a risk of injury.
Three police officers recently volunteered to demonstrate the effectiveness of the taser - an electrical weapon fires two barbs into the offender with a force of 50,000 volts - at police trials.
Although none of the officers suffered any lasting effects, records obtained under the Official Information Act showed that two suffered minor flesh wounds and one was dazed after falling badly and hitting his head, despite controlled conditions.
Critics say it highlights the risk of using the stun guns.
"Imagine what it's going to be like in the real world, not the padded floor at the police college, where people are going to be tasered in stairwells, on the tops of buildings, on concrete roads and paths," says Campaign Against the Taser spokesperson Marie Dyhrberg.
Even police are acknowledging the risk of head injury.
"The possibility that a person would fall and sustain secondary injuries is real, and there is no sort of way around that I'm afraid to say," says superintendent John Rivers.
But they insist that the taser is a "safe device."
However opponents are preparing to step up the fight.
"Now that we know what's been happening with the behind-the-doors trial, we're certainly going to be raising it again with the minister in the house," says Maori Party spokesperson Hone Harawira.
The taser is currently being trialled for a year by 180 officers
in Auckland and Wellington.