VANCOUVER — While B.C. lawyers were telling Canada’s highest court that the province’s strict drunk-driving law has saved many lives, the government had access to research calling that conclusion into question.

A draft ICBC report prepared in January 2015 suggests that B.C.’s automatic roadside prohibition scheme may have contributed to a decline in the number of fatal crashes by about 36 per year since September 2010.

But to confirm that finding, the consultant who prepared the report would have needed control data showing the trend in collisions over the same period if the so-called Impaired Driving Initiative wasn’t in place. Since nobody in the province is immune from the law, that would be impossible.

“Without such data, it would not be possible to say whether any observed changes in collision frequency over time were due to the IDI or to the many other factors (e.g., weather, other road safety enforcement initiatives, traffic density, road improvements, availability of public transportation, etc.),” the draft reads.

Instead, the consultant compared crash data from before and after September 2010 in five communities to produce a “descriptive study” of the law’s impact.

The report was released this month in response to a Freedom of Information request from Vancouver law firm Mulligan Tam Pearson — nearly a year after the request was first made. It came with a letter from ICBC’s privacy adviser apologizing for the delay but offering no explanation for the long wait, which far exceeded the legal time limit of 30 days for a response.

According to defence lawyer Michael Mulligan, exceeding the time limit isn’t the only issue with the late response.

“It’s a problem because that legislation has been considered in various ways during the intervening period of time when they didn’t provide disclosure of the information,” he said.

For one thing, he thinks the report should have been disclosed before government lawyers headed to the Supreme Court of Canada to argue in favour of the law. In October, the high court upheld the latest version of the legislation, which was redrafted in 2012 after a B.C. Supreme Court ruled it unconstitutional.

“Part of the government’s submission there was the effectiveness of the legislation …. ‘This is successful, look how many lives it’s saved,’” Mulligan said.

“There can be reasonable debate about the conclusions that ICBC’s report reached, but it certainly seems to me that it’s questionable whether that is so or not.”

Meanwhile, Justice Minister Suzanne Anton said this fall that the law had saved 260 lives since it was brought into force, a conclusion that Mulligan doesn’t believe is adequately supported by the report.

According to the Ministry of Public Safety, Anton’s number was calculated in much the same way as ICBC’s figures, by comparing RoadSafetyBC data on fatal crashes for the five years before and after the law was brought into effect.

The ICBC report didn’t include any estimates of the law’s impact on non-fatal crashes because of a lack of comprehensive data from both the insurance corporation and police. ICBC claims don’t include contributing factors in crashes, while police officers aren’t called to attend every collision.

But it does suggest that if the estimates of lives saved are accurate, the law has helped to save about $8.4 million each year.

In an emailed statement, ICBC spokeswoman Joanna Linsangan did not offer a specific explanation for the delay in releasing the report to Mulligan’s law firm, but said it is not always possible to meet deadlines considering the “large volume” of requests received by the Crown corporation. She added that ICBC fully supports the province’s efforts to combat impaired driving.

blindsay@postmedia.com

Twitter.com/bethanylindsay

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