Olivia Chow thinks all trucks need side guards on their trailers and she is introducing a bill in Canada's Parliament to try to make it a reality.

Chow, of Canada's New Democratic Party, is a member of the Canadian House of Commons, and it's not the first time she has attempted to have this law passed.

This time though, as the widow of the late NDP Leader Jack Layton and as the NDP's Transport Critic, Chow is exploiting the tragic death of a Toronto mother who was in an accident with a truck on one of the city's busiest main streets last week.

No charges have been laid in the accident. Police are still investigating.

The Canadian Trucking Alliance says it's far from clear whether such a law would save lives or lead to less serious injury of bicyclists. And, says the alliance's president, David Bradley, CTA's opposition to the bill has nothing to do with cost or competitive issues, as Chow suggested in recent media reports.

Bradley points to a March 2010 study conducted by the National Research Council for Transport Canada which concluded "it is not clear if side guards will reduce deaths and serious injury of if the guards will simply alter the mode of death and serious injury" and "cyclist advocates who have stated that the biggest problem is a lack of awareness of how to safely share the road with other vehicles and bike lanes which would separate cyclists from other traffic."

"This is a complex issue," says Bradley. "While we fully understand the emotions that would be cause for some people to support mandatory side guards, we feel the solution lies elsewhere - in increasing awareness and education and planning for bike lanes."

He also said there needs to be a distinction made between trucks operating in inner-city areas and tractor-trailer units that operate on highways. "Very seldom, if ever, will the vast majority of tractor-trailers operate downtown; they are unlikely to ever encounter cyclists," he says. "Does it make sense that tractor-trailers be required to install side-guards?"

Bradley also notes that an increasing number of tractor-trailer units are being equipped with side fairings which reduce aerodynamic drag, thereby improving fuel economy and reducing GHG emissions. The National Research Council study found that the kind of side guards contemplated in Chow's bill "would be detrimental to the drag coefficient of highway vehicles travelling at higher speeds."

According to figures from Transport Canada, there are about 221,000 registered commercial highway tractor-trailer units in Canada. Given that most trucking companies have at least a 2:1 tractor-trailer ratio, that would mean that at least 442,000 trailers would need to have side guards installed on them.

Bradley says he is disappointed that Chow is using the introduction of her bill to cast aspersions on the trucking industry. In at least one media report she suggests that cost is the issue, and is quoted in the Toronto Star as saying the federal transport minister "is only hearing the voices of the trucking industry."

But, says Bradley, "CTA has a clear track record in advocating for the mandatory installation of technologies and devices that are proven to improve highway safety, such as speed limiters on all trucks, electronic on-board recorders to monitor compliance with truck driver hours of service rules and roll-stability systems. And, for the record, CTA has never been invited to discuss side-guards with the current minister or any other minister in at least the previous 25 years. Nor has Ms. Chow ever discussed the issue with us."

CTA has worked with cycling advocates to improve road safety and awareness of sharing the road with trucks.