The rules, introduced in September 2010, meant that police could impose an automatic 90-day driving ban and a $500 fine for anyone who refuses a breathalyzer test or blows over the 0.08 blood alcohol level limit.
Police also had the power to impound vehicles for 30 days, and impose driving prohibitions if a driver's blood alcohol level is found to be over 0.05.
In 2012, a court challenge forced the B.C. government to change the rules around immediate roadside suspensions, giving drivers an opportunity to appeal roadside breathalyzer results.
But proponents agree that the system still works. Vancouver police Const. Brian Montague said it appears, anecdotally, that fewer people are driving drunk in the city.
"We have the same number of officers that are out and about, we're stopping the same amount of people, and yeah, the number of impaired drivers we are seeing appears to be in decline," he said.
Restaurants support changes
Initially, bar and restaurant owners were frustrated with the rules, and felt that some diners were wary of ordering a drink with dinner. Two months after the rules went into effect, the B.C. Restaurant Association estimated that some businesses saw sales drop between 15 and 30 per cent.
Less than a year later, the association changed its mind. Ian Tostenson, president of the B.C. Restaurant Association, says people have adapted.
"These tougher drinking driving regulations are good, and it just takes time," Tostenson says. "What we said at the time was give us some time to adjust, not surprise us overnight."
The province and the RCMP also say the measures are paying off. The RCMP estimate that at least 100 lives have been saved after people changed their behaviour as they adapted to the rules.
That estimate is based on five years of data collected by ICBC, which captures the number of traffic deaths where impairment by alcohol, drugs, or medication was deemed a factor.
The year after the penalties were introduced, the number of driving fatalities relating to impairment dropped sharply — and dropped more sharply than the decline in numbers of fatalities linked to other causes, such as speeding, being distracted, taking risks, or driving too fast for road conditions. (See chart below.)
MADD wary of trend
Despite the encouraging trend, Mothers Against Drunk Driving isn't convinced the fix is permanent.
Bob Rorison, spokesman for MADD Metro Vancouver, said that as the novelty of the new regulations wears off, more people will start drinking and driving again.
"We've had a lot less deaths from drinking and driving and injuries, but let's see what happens in the future," Rorison said.
"People have forgotten the message. They think that it won't be them, they don't get stopped every day, we don't have check stops everywhere, so they still think that they can get away with it," he said.
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