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A DUI detector in every car?

By Claes Bell ·
Tuesday, February 1, 2011
Posted: 1 pm ET

It looks like the federal government may one day require you to take a sobriety test every time you start your car (from the Associated Press):

An alcohol-detection prototype that uses automatic sensors to instantly gauge a driver's fitness to be on the road has the potential to save thousands of lives, but could be as long as a decade away from everyday use in cars, federal officials and researchers said Friday.

U.S. Transportation Secretary Ray LaHood visited QinetiQ North America, a research and development facility based in Waltham, Mass., for the first public demonstration of systems that could measure whether a motorist has a blood alcohol content at or above the legal limit of 0.08 and -- if so -- prevent the vehicle from starting.

The technology is being designed as unobtrusive, unlike current alcohol ignition interlock systems often mandated by judges for convicted drunken drivers. Those require operators to blow into a breath-testing device before the car can operate.

My first instinct here was to criticize the idea. Not only would it add even more expense to the price of new cars, but it's more than a little bit eerily authoritarian to have to submit to a sobriety test every time you start your vehicle.

And there's a presumption of guilt there that I'm not 100 percent comfortable with, as if the only thing standing between me and plowing into another car in a drunken stupor is the benevolence of the federal government in subjecting me to a sobriety test.

Alcohol detectors built into cars could spell the end of the after-work happy hour for many.

DUI detectors built into cars would keep them from starting if drivers had more than a preset level of alcohol in their systems.

But then I started thinking about it in terms of managing risk. There are plenty of doohickeys that are mandated in our vehicles to help reduce risk: turn signals help reduce the risk that we won't see a car turning into our lane until it's too late, seat belts help reduce the risk we'll sustain terrible injuries in an accident, and air bags help reduce the risk we'll be injured because we forgot to put on our seat belts.

The risk that someone will intentionally or inadvertently engage in drunken driving is another risk worth minimizing, especially if we can do so relatively painlessly. Despite the fact drunken driving awareness and enforcement are at really high levels, there are still people who habitually get behind the wheel of a car drunk and kill people -- 10,839 Americans in 2009 alone. And even if you had really good DUI, or driving under the influence, enforcement that allowed you to get every habitual drunken driver off the road, you'd still have drunken driving.

That's because it can sometimes be difficult even for responsible people to know when they've crossed the drunken-driving line. The simple rule of thumb that each drink raises your blood alcohol level 0.02 can certainly help, but so many factors affect how alcohol affects the human body: whether it's consumed on an empty stomach, your body weight and composition and even whether you're dehydrated.

And the feeling of intoxication is indisputably subjective. Do you feel that different at 0.06 percent blood alcohol content than at 0.08, the legal threshold beyond which you're committing a serious crime?

In that sense, an automatic sobriety test doesn't assume you're a habitual drunken driver, it assumes that knowing when you're OK to drive and when you need to call a cab can be pretty hard. If such a system saved you from accidentally driving once you've become a danger to yourself or others, or saved you the $10,000 it costs on average to deal with a DUI, wouldn't you be happy you had it?

On the other hand, it's hard to know where the cutoff will be set by regulators. Will it be at 0.08 percent, the standard for a DUI? Or will it be lower, to reflect the belief that driving is impaired at blood alcohol levels far below the legal limit? If it's the latter, you can probably say goodbye to a couple glasses of wine with dinner or the after-work beer.

What do you think? Does standard sobriety testing in every car cross a line, or is it a good idea?

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Claes Bell
February 02, 2011 at 9:04 am

Lots of good comments here. I think you're right that transportation alternatives would go a long way toward solving the DUI problem. Sure in a big city it's not an issue, but if you live in a small town, the only way to get home a lot of times is your own vehicle or a friend's vehicle. Nick, that's a great point. The sensors that are meant to detect trace amounts of alcohol in the car might get a false positive from an inebriated passenger. And Shantique, the malfunction issue is another thing that occurred to me after I wrote the post ... imagine having to pay $300 to replace a malfunctioning DUI detector in your car!

February 02, 2011 at 8:20 am

I hear stories about people cheating these devices all the time (my father was a cop). Often people have their children take the test, and then proceed to drive drunk with their kids in the car! It's disgusting. This would just be an extra step and waste of time for people that are good. AGAIN, punishing the overall good for the few bad seeds. Those bad seeds would be the ones trying to work around it...not the good people. So it would defeat the purpose, cost me more money to buy and take more time out of an already strapped for time life! Not to mention it's one more thing that will require repair and maintenance! Imagine trying to start your car to go to work in the morning, and the thing malfunctions!

IF I thought this would truly save lives I would be all for it...but it won't bc people that drive drunk have NO respect for their lives or the lives of others, so they would cheat the system anyway!

February 02, 2011 at 7:26 am

I'm all for this. My only question would be, assuming the "unobstrusive" sensor is placed on the dashboard or steering wheel, would it be able to distinguish between the driver and anyone else in the car who may have been drinking?

February 01, 2011 at 3:13 pm

I do not think it is fair to subject all motorists to a DUI test without providing some sort of transportation alternative. Many people would rather be able to take a bus or other transportation to and from bars or parties if only it was economic and available. I think that you have to have a carrot AND a stick. Just mandating all cars have sobriety testing will force otherwise law abiding people to find ways around it. I am sure there will be a way to dismantle the DUI tester about 15 min after it rolls off the assembly line. The only way it will work to effectively reduce the risk of drunk driving is if it is combined with alternative forms of transportation.