The ACT government should leave helmet laws alone and build safer infrastructure separating cyclists from traffic if they want more people to ride bikes, the co-author of a review into the effectiveness of helmets says.
An expert will investigate the risks and benefits of allowing cyclists to ride without helmets in "low speed environments", such as shared zones and university campuses, as part of a suite of 39 initiatives proposed in the ACT Road Safety Action Plan to help reach a goal of zero road deaths.
But University of NSW Road Safety Professor Raphael Grzebieta said there was "extensive Australian literature" that showed a no-helmet rule would only have a "minor influence" on the uptake of bike riding.
"The main reason people aren't riding a bicycle is the danger of interacting with cars and trucks on roads," he said.
"What governments are reluctant to do is build bicycle infrastructure that segregates cyclists from traffic.
"If you mix cars and bicycles, cars must travel at 30km/h or less, that's what they're doing in Europe, that's world's best practice."
Professor Grzebieta, and his co-authors, used crash and injury data from NSW to conclude wearing a helmet reduced the risk of head injuries by up to 74 per cent, in a 2013 peer-reviewed study cited in the Action Plan released on Monday.
The no-helmet rule is one suggestion to increase the take-up of cycling over cars, which Road Safety Minister Shane Rattenbury believes will make roads safer.
Pedal Power executive officer John Armstrong said the advocacy group was ambivalent about the move, but said there was evidence introducing mandatory helmet laws reduced the percentage of bike riders.
"We absolutely recognise the safety outcomes of wearing a helmet, but the introduction of helmet laws in 1992 did coincide with a 25 per cent reduction in the number of people who chose to ride a bike," he said.
Mr Armstrong said Mexico and Israel recently enforced helmet wearing, only to repeal the laws within two years to boost cycling numbers from 2 per cent to 5 per cent, but he said more research was needed before the ACT followed suit.
NRMA ACT director Kate Lundy agreed, and said a no-helmet policy would have to be evidence-based.
She was unconvinced having more cyclists and public transport users would lead to a reduction in road deaths.
"There's a lot of great reasons to have more public transport and to cycle, but it doesn't change anything from the need for a very strong commitment to improving road safety through driver education… the engineering of roads… and cycleways," she said.
Mr Armstrong said intersection upgrades, adopting the outcome of the vulnerable road users' inquiry, and building more training facilities and education for young cyclists would have a greater impact on road safety than the review of helmet laws, but the success of the initiatives would hinge on funding.
"Our stats for children under 10 [riding bikes] are below the national average… and we need to address this," he said.
While it would be difficult to enforce helmet wearing in some areas and allow riders to go without in others, Mr Armstrong said the Northern Territory had a higher proportion of bike riders as it allowed riders to go without helmets on share paths.