A cyclist could be fined $55 for not wearing a helmet and it has been mandatory in New Zealand since 1994.
Superintendent Stephen Greally said safety on the road was a priority for police, whether the road user was in a car, on a bike, or using some other form of transport.
"There has been no change in the way police enforce laws for bicycle related offences," he said.
"When an officer attends a job, they are responsible to assessing the situation and providing an appropriate response to ensure the safety of the public.
"The response from an officer could range from an infringement notice to a warning or prevention advice, this decision is made at the officer's discretion."
Mr Oliver said helmet use should be a personal decision for adults, and said he'd estimate around 80 per cent of Bay cyclists do.
"Personally, I'd never not wear a helmet.
"You only have to have a situation... where people's inattention creates accidents, and you're in trouble. If you haven't got a helmet on, you're quite likely to be dead."
He said "1 in 1000" serious cyclists would bike without a helmet, and it tended to be commuters and casual riders who didn't.
Nationwide, fines for failing to wear a helmet halved in the past three years, from 9936 to 4748 last year.
Cycling Action Network's Patrick Morgan agreed the fall in helmet infringements seemed to be a result of changing police priorities.
"I think it's just police have better things to do than stop people on bikes and fine them for helmet use or misuse," Mr Morgan said.
"I welcome police resources going into higher priorities."
Mr Morgan says there is "thin" evidence that mandatory helmet use laws work, and that Australia and New Zealand are the only two countries that have such a law.
"There's enough evidence that mandatory bicycle helmets hasn't worked as intended, and that's why it's our policy to review the law, to see if it's working as intended - but it's not our top priority."
He said CAN's position was not a call for making helmets optional, but to review the wider effects of helmet-wearing legislation.
Mr Morgan said he doesn't normally wear a helmet when cycling on the road. He has a legal exemption - on medical grounds as he said helmets gave him headaches and migraines. He said he was stopped three or four times per year.
"I wear it if I do something dangerous, like mountain biking or something risky like that. But [not if I'm] just riding around my neighbourhood or on a separate New Zealand cycle trail."