By Jordan W. Charness

“What are you doing between midnight and 3 a.m. tonight?” was the question. “Sleeping, I guess,” was my answer. At the time it seemed like a perfectly reasonable answer. But you never know which way life is going to take you.

My interlocutor in the present instance was my good friend Sgt. Gerald McGrath of the Montreal police force. He is not usually interested in my sleeping habits and his next sentence explained why he was. “We’re going to do a roadblock tonight in your area and you’ll probably learn something if you tag along.”

Now is the season when people tend to party. Holiday parties abound, and in general people are trying to get themselves into a more cheery mood. This cheeriness often involves alcohol. Sometimes these “cheery people” get behind the wheel of their cars and drive. We all know that this is illegal. It’s also a really bad idea.

Right about now our local police run several activities to help persuade people not to drink and drive. One of the most visible and effective is the roadblock. Although the police usually need a reason (probable cause) to pull you over, the courts have ruled that a roadblock operation where everyone in that spot is stopped and checked for visible signs of alcohol is legal even when there is no probable cause.

So there I was at midnight on a weeknight along with eight of Montreal’s finest setting up a roadblock. There are several ways to do so. The most common is to divert all traffic into one or two lanes and then stop each driver for a brief chat. If the police officer notices a hint of alcohol on a driver’s breath he may be asked to pull over and blow into a breathalyser machine.

Once I was there, I decided to take the test myself and see how the portable machine works. The newer machines are about the size of an electronic organizer and are extremely easy to use. They’re calibrated every two weeks to be sure that they read accurately. They only have three readings: pass, warn and fail. As I understand it, if you have anywhere from 0 to 50 milligrams of alcohol per 100 ml of blood, the machine will give a pass reading. Between 50 and about 100 you’ll get a warning light and if it reads 100 or over, the machine will tell you that you failed.

As you should know by now the maximum amount of alcohol that you’re allowed to have in your bloodstream is no more than 80 milligrams per 100 ml. The roadside breathalysers cannot give a pinpoint-accurate reading and are therefore calibrated so that if you fail you definitely have more alcohol in your bloodstream than you’re allowed to have.

The machine is very easy to blow into and takes virtually no effort at all. Even someone with asthma should have no difficulty blowing into the machine. You only have to blow for a few seconds until it clicks and lets you know that it has taken a reading. If you don’t blow hard enough it will tell you to do it again. If you try to fake it you’ll get no reading and be asked to take the test again. If you refuse or fail to blow properly you’ll be charged with failure to blow which is as serious a criminal charge as drinking and driving.

The whole test is very hygienic and quick. The mouthpiece is a special straw individually wrapped and used only once. My test took about 10 seconds and almost immediately came back with a 0.0 reading, proving that I really had not had anything to drink that night.

In order to be allowed to administer a portable breathalyser test, the police officer must have passed a one-day training course in the use of the machine and its related regulations. Most police officers in Montreal take the course as part of their basic training. Each local police station has a few of these portable machines.

In three hours a roadblock operation like this one could stop around 200 cars. Usually the police officer who stops you is the one who asks you the questions and if he or she becomes suspicious as a result of your answers, they will administer the test. The same officer is also one of two police officers who escort you to the detention centre where you will take the breathalyser test that will give an extremely accurate reading that is valid as evidence against you in court.

Just because the roadside test is not 100 percent accurate does not mean that you can talk yourself out of being detained. If you fail the roadside breathalyser the police must bring you to the detention centre for the big test. It’s only if you fail the big machine’s test that you will be charged with the criminal offence of driving with too much alcohol in your bloodstream.

Next week, join me as I watch the entire procedure, from stopping a suspected drunk driver to her eventual release from the police station: you’ll be surprised at the results.

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