The Opposition says it is concerned a new policy tightening the criteria for the use of tasers by police is ambiguous.

The Police Commissioner Karl O'Callaghan has announced officers will have to believe they're at risk of serious injury before using a taser, rather than just being verbally threatened or pushed and shoved.

"If someone came at you with a broken glass, if someone came at you with a weapon, if someone had a stick in their hand," he said.

Labor's Margaret Quirk says she welcomes restrictions on the use of tasers but believes it's policy on the run.

"I am concerned that the criteria may be a bit ambiguous for officers on the frontline," she said.

"There will need to be I think considerable discussion and guidance about those guidelines before officers can feel confident that they'll be backed up if they have to use the tasers."

The Police Union president Russell Armstrong says the comissioner's announcement has upset officers.

"They've said that they should hand their tasers back and we'll start carrying our batons and only our firearms," he said.

Mr O'Callaghan says the policy will be trialled for up to six months.

He also announced an audit of all 'use of force' incidents captured on CCTV to ascertain whether the police account matches what is on the tape.