The better part of a year after Parliament passed laws setting blood limits for cannabis and other drugs, police are making little use of them.

Police in Alberta have laid only eight charges under the new laws, and none at all in B.C.

Ontario and Quebec show a different pattern. In those provinces, the new charges are being used to some extent — Ontario has laid exactly 100 up to the end of June, and Quebec 39.

But they’re very rarely seen in big cities.

Quebec’s 39 cases skew heavily to small towns — the provincial court in Percé, on the eastern tip of the Gaspé, is handling seven charges under the new law, while Montreal and Quebec City have only one each.

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Ontario is similar. About a third of the charges for exceeding a drug limit were laid by Ontario Provincial Police detachments, which serve rural and northern parts of the province. Toronto police have laid two, the same as the OPP’s Huron County detachment.

The only big-city Ontario police force to have laid any significant number is Hamilton‘s, with 15, figures released by the province show.

“I think it’s really interesting to see that the law isn’t really being applied uniformly across the country,” says Vancouver criminal lawyer Sarah Leamon. Tweet This

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“I did have an inkling of that because I didn’t think that we were charging for THC per se limits (THC blood limits for drivers) in British Columbia. I hadn’t seen any charges so I’m not surprised to see that, but I am surprised to see how much discrepancy there is between provinces.”

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The main problem with charging a driver under the new drug limits is the need for a prompt blood test, says Toronto police Sgt. Warren Stein.

“It’s extremely complicated, and that’s why we don’t use it very often,” he says. “It’s literally the last resort.” Tweet This

One problem is that a suspect has to be brought to a hospital and have blood taken within two hours of the original incident, Stein explains.

“In the city of Toronto, it’s a stretch. By the time you go through your roadside vehicle impoundment, get the person to the hospital, through the triage, to the doctor — if the doctor agrees to take the blood — draw the blood, that blood draw has to be within two hours,” he says.

“If everything goes perfectly, you could probably make it in the two hours, but if you have one hiccup along the way, you may be outside that two-hour window and then you cannot use the results of that blood.” Tweet This

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Often, a busy emergency ward just can’t fit it in.

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“We understand that the doctor’s first priority is ill patients. When we come in with an impaired [driver], that is not a medical emergency,” Stein says.

More commonly, he says, police get a warrant for a sample of blood that was taken for medical reasons.

Under the new laws, drivers can be charged for having blood levels over two nanograms of THC per millilitre and face more serious penalties at over five nanograms. At the higher level, mandatory minimums require jail time after the first offence. A different offence deals with drivers impaired by alcohol and a drug at the same time.

“Smaller towns that have a relationship with their one hospital, if you have that relationship, they may get it through much faster, and the doctors are more willing to pull him in through triage, get the blood drawn and off to the Centre for Forensic Sciences for the analysis,” Stein says.

“I can see it being much more practical for the smaller communities.” Tweet This

The OPP did not respond to a request for comment.

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Most of the Ontario charges are still making their way through the courts, which means that challenges to the Draeger 5000 — until recently the only federally approved device for screening drivers for THC — have yet to be heard. (The Draeger is only used to identify divers that need more formal scrutiny, not to get a measurement that could be used in court.)

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Critics of the device say it works poorly in the cold and can show a positive test for opiates in someone who has been eating poppy seeds. (Draeger defends its device.)

The only major Ontario force to have adopted the devices on a large scale is the Ontario Provincial Police. The Ottawa force passed on them, and the Toronto police only have eight. Some smaller forces, like those in Cobourg and Cornwall, are using them.

“It’s another tool available to police officers in order to detect impaired driving at the roadside,” Leamon says. “Whether that’s actually going to hold up to constitutional muster is a completely different question. I don’t think that it will, just because I don’t think the technology is there yet — and may never be there.”

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In the meantime, Toronto police are trying to work out a way of getting blood from drivers that doesn’t involve taking them to busy hospitals and hoping for the best. (Police in Arizona, trained to draw blood, can do it at the roadside in a specially equipped van.)

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“We’ve started looking at it,” Stein says. “We’ve been talking to the Ministry of the Attorney General about it. There could be arrangements made with private labs to have phlebotomists being utilized to draw blood.

“There are certain legal hurdles to jump through, which is making it difficult to implement, as well as who pays for it. But definitely, that is a conversation that is happening.”

Ontario’s Ministry of the Attorney General did not directly respond to questions about plans to make blood tests easier.

‘Police services are responsible for the investigation and laying of criminal charges and they have a variety of investigative tools at their disposal to detect and apprehend drug impaired drivers,” spokesperson Brian Gray wrote in an e-mail. “Only a few of these require blood samples. Ontario has already drastically increased the number of officers trained in detecting drug impaired drivers, and is continuing to train more.”