Dozens of people accused of drinking and driving in Alberta are getting off without a trial, according to a Calgary lawyer.

Defence lawyer Tim Foster, who specializes in impaired law, says some Alberta judges are dismissing cases because Crown prosecutors have been refusing for years to hand over the key evidence of breathalyzer machine maintenance records. 

hi-bc-110714-breathalyzer

Defence lawyers who do not receive the maintenance files for a breathalyzer can submit a charter application arguing their client's rights were violated because there was no confirmation it was working properly. (CBC)

"If my defence is to show that it wasn't maintained properly and yet the police and Crown conceal the evidence about whether it's maintained properly, it's really hard to win those battles," said Foster.

The results of a breathalyzer test tells police whether or not a driver has been drinking by reading a person's blood alcohol level. 

In Alberta, drivers who blow a blood alcohol level between .05 and .08 lose their licence and vehicle for three days for a first offence. With each offence, the penalties become harsher. Drivers who blow over 0.08 are criminally charged. 

The breathalyzer results are powerful proof that hold a lot of weight in court and just about the only evidence that can discredit its findings are maintenance logs for the machine.

"Unless you can show the instrument wasn't operated properly, unless it malfunctioned or that it wasn't maintained properly," said Foster. 

"In order to show that it wasn't maintained properly, we need these records."

Defence lawyers like Foster who do not receive the maintenance files for the breathalyzer can submit a charter application arguing their client's rights were violated. 

Foster estimates in the Calgary area alone, 50 cases were tossed out before he won a case in the Court of Queen's Bench in January of this year called the Kilpatrick decision.

Ruling supposed to set precedent

The judge ruled the maintenance records must be handed over and it was supposed to set the precedent provincewide.

Foster says Calgary Crown prosecutors have complied, but there are other Alberta jurisdictions where he is still fighting for the information.

"When you have a society where you decide guilt and innocence in a court according to rules, it's pretty hard to go into a battle with one hand tied behind your back," Foster said.

Alberta Justice declined an interview request but provided a statement in an email.

It says the issue of disclosing maintenance records in impaired driving cases is the subject of ongoing litigation in the province. 

They did not want to make prosecutors or the justice minister available for an interview as the matter is before the courts and it did not want to be seen as trying to influence the court's decision through the media.

Greg Lepp, the head of Alberta's Prosecution Service, said in the statement they do comply with recommendations from the Alcohol Test Committee (ATC) of Canada.

The ATC is tasked with evaluating all scientific breath testing devices and making recommendations on proper operation and maintenance.

"In the Crown's view, these recommendations provide for the disclosure of all relevant information needed for accused persons to make full answer and defence without burdening police agencies and Crown offices with providing irrelevant material," he wrote.

Alberta's Prosecution Service says once the law is settled in all jurisdictions, it will review disclosure practices and comply with any legal obligations.