An international study of more than 64,000 injured cyclists has apparently laid to rest the assertion that bicycle helmets can cause head and neck injuries to their wearers.
The research by two Australian statisticians drew together data from more than 40 separate studies, and concluded the reverse was the case. Cyclists who wore helmets reduced their risk of fatal injury by about 65 per cent.
According to the study, conducted by the University of NSW, wearing a helmet reduced the risk of head injury by 51 per cent, serious head injuries by 69 per cent and facial injuries by 33 per cent.
While legislators and enforcement officers would doubtless be hoping this will silence the small, but vocal, minority of riders who regularly refuse to wear a helmet on safety grounds, this may prove overly optimistic.
While the report's authors have said their findings "do not support arguments against helmet legislation from any injury prevention perspective" they do acknowledge its major limitation.
That is its inability to reach out to the many would-be cyclists of both sexes who choose not to use their bikes for day-to-day transport, as opposed to use as a weekend or after-work exercise device, because they don't like helmets.
These issues are of particular interest in Canberra, already one of Australia's most bicycle friendly cities, with cycling featuring prominently in both Labor and Liberal transport policy.
The strongest argument against Australia's mandatory bike helmet laws, which first took effect in Victoria in 1990 and were enacted here in 1992, is the impact they have on the cycling participation rate.
Mandatory helmet opponents regularly claim that if helmet wearing was not compulsory many more people would ride on a regular basis.
This, they say, would have two major health and safety benefits. The first is more people would be getting more exercise and as a result the population would be healthier overall.
The second, and less easily proved benefit, is the "safety in numbers" argument. Proponents of free choice believe the more bike riders there are, the safer all bike riders become. This is because motorists would be more aware of cyclists as there would be more of them.
That claim does appear to be open to debate given a 2011 National Heart Foundation study ranked having to wear a helmet at 13th on a list of 15 reasons given by people for not riding a bike for transport more often.
Unsafe road conditions, the speed and volume of traffic and concerns about safety were the three main reasons people chose not to ride.
In light of this it would be reckless for any government to amend its helmet laws in the expectation of a sudden boost in cyclist numbers without commissioning rigorous research on the matter.