The number of drunk driving charges laid since B.C.'s unforgiving impaired driving regime was put on hold last November has fallen to a mere fraction of those sworn before the now-defunct law was implemented, CTV News has learned.

In 2009, before B.C.'s tough drunk driving legislation took effect, an average of 671 impaired driving charges were laid per month.

In December 2011 and January 2012, the two months after parts of the law were struck down in B.C. Supreme Court, the monthly average plunged to just 177.

Bob Rorison of Mothers Against Drunk Driving said the new figures are troubling, and could signal rocky roads ahead for motorists in the province.

"My concern is we're having to share the roads with more drunk drivers," Rorison said. "It'll be interesting to see if the death and injury rate actually increases during this period of time – and that's really how we really count our success, we count the bodies on the side of the road."

B.C.'s new impaired laws, established through Motor Vehicle Act amendments, came into effect in October 2010, giving police the power to issue immediate 90-day driving bans and levy thousands of dollars in fines and costs to anyone caught blowing over .08 in a roadside breathalyzer test.

In the first year under the new law, commonly described as the toughest in Canada, the provincial government touted a 40-per-cent decrease in alcohol-related deaths. More than 15,000 immediate roadside bans were issued for people who blew a fail or refused to blow into the roadside screening device.

But that system hit the brakes last November, when B.C. Supreme Court Justice Jon Sigurdson ruled parts of the legislation unconstitutional, effectively forcing police back into the time-consuming process of laying criminal charges.

Sigurdson gave the government six months' grace time to amend parts of the law to ensure a "reasonable and meaningful review process" that would allow drivers to challenge their roadside readings.

Though charges since appear to have slumped significantly compared to 2009, Attorney General Shirley Bond said the numbers may reflect a change in the zeitgeist.

"I am hopeful that it's a change in culture, and I've had people tell me that they think twice now before they drink and get into a vehicle," Bond said.

Bond added that she's spoken to police across B.C. and is confident that the drop has nothing to do with lax enforcement.

"The statistics, you can look at them a number of ways… What I want to do is make sure that we've got a stringent regime in this province," Bond said. "Law enforcement officers across the province are continuing to be aggressive."

Supt. Norm Gaumont, head of RCMP traffic services for the Lower Mainland, said two months' data is not enough to warrant speculation about any trend or pattern, but police haven't seen a severe increase in impaired driving deaths since November.

"Our fatal data has not skyrocketed back up. We're not seeing that, and we're certainly watching it closely," Gaumont said.

"I'd say wait another six months and see where we're at."

November's B.C. Supreme Court ruling found the less-severe fines, driving prohibitions and penalties associated with blowing in the blood alcohol warning range between .05 and .08 were also unconstitutional, but justified.

With a report from CTV British Columbia's Mi-Jung Lee