A person who has been convicted of drunk driving may be required by law to install an ignition interlock device on their vehicle. This prevents them from getting behind the wheel when their blood alcohol is above a certain limit.
This may be set below the legal limit for a conviction for driving under the influence. While the installation of such a device might be required after a first-time offense, it is more likely to be ordered after multiple DUI offenses.
What is the Technology?
Older-style devices used semi-conductor technology for the tests. However, these were often inaccurate and resulted in false positives. Because the results of a test have serious legal implications, this inaccuracy was a problem.
Today, most devices use fuel cell technology. The fuel cells act as sensors that detect the presence of alcohol. The alcohol is converted via oxidation to an electrical current that can be measured.
The results of the test are recorded. Law enforcement may periodically review these results. Furthermore, the car will not start without a blood alcohol level that is below the limit that has been set.
How Does it Prevent Drunk Driving?
As is the case with a Breathalyzer test, an ignition interlock device requires the driver to blow into it in order to measure their blood alcohol content. However, the device does not restrict itself to only testing a driver at the time that they are starting the car.
In order to prevent a driver from keeping alcohol in the vehicle and drinking after the car is in motion, a device can also require what is called a “running retest” or “rolling retest.” This requires the driver to take the test again.
The driver may be able to pull the car over in order to retake the test, but the rolling retest is also safe if done while driving. The results are recorded, and the device may prompt the driver to pull over if they fail the retest.
What Are The Legal Implications?
The legal implications for a record that shows a person made multiple attempts to drive while intoxicated may be severe. A person may face further penalties.
Another imposition is that an individual must pay for the ignition interlock install. Furthermore, there are maintenance fees, and the device must be serviced regularly. A person might avoid a more severe penalty with the installation of the device, but this does not come cheaply.
How Does It Change Behavior?
An ignition interlock device prevents drunk driving by not allowing a person to operate a vehicle when above a certain blood alcohol content level. Unfortunately, for some people, the result does not significantly alter the attempt to drive while under the influence although it does physically prevent them from doing so. However, people who have had such a device on their cars are more likely to carry a personal device to monitor their blood alcohol content.
Given the inconvenience placed on a driver who has to use such a device and the cost of an ignition interlock install, this may act as a powerful deterrent to drunk driving and can be a significant tool in the effort to make roads safer.
