These devices are installed inside a vehicle and require the operator to pass a breath-alcohol test to determine impairment. If the driver’s breath-alcohol content is measured above a certain threshold (usually 0.04 percent, or half the legal limit), the ignition locks and the vehicle will not start.
However, the positive effects of these systems are limited to how long they are actually in place. Because they are imposed as a penalty for DUI conviction, they are almost always temporary. But researchers with the University of Michigan Health System wanted to know what would happen if the devices came standard in all new model vehicles – permanently, and not just for those drivers who were being punished.
The results, published in the American Journal of Public Health, are astonishing. Over the course of 15 years, we could potentially reduce the number of drunk driving fatalities and injuries by 80 percent. In real terms, that would be 59,000 lives saved. It would be 1.25 million people spared serious injuries. It would mean $340 billion saved in injury-related costs associated with drunk driving accidents.
All of this assumes the calibration would be set at 0.02 percent breath-alcohol content (instead of the current 0.04 percent), as well as 100 percent accuracy of the devices.
Although there would be an initial cost of $400 per vehicle to have each device come standard in all new vehicles (it would not be retroactively installed), those costs would quickly be recovered within three years.
The study’s lead researcher, an emergency room physician, noted that while alcohol interlocks are used effectively in all 50 states as part of the solution for criminal sentencing in DUI cases or as a condition of license reinstatement, they only work if drunk drivers are actually caught by police in the first place. Another study by Mothers Against Drunk Driving had shown the average person drives impaired 80 times before being arrested on any type of DUI charge.
What’s more, the system will not help catch those individuals who are driving without a license to avoid having the devices installed in the first place.
If auto manufacturers started making ignition interlocks standard in all vehicles, it would be an effective solution that would cost little time and effort. In fact, we would be spared a significant amount of resources in terms of our police forces, which routinely must conduct sobriety checkpoints and other enhanced patrols in an effort to catch drunk drivers. In fact, drivers who are drunk would never be able to get the car to start in the first place.
Researchers with AAA said they would support such a measure, assuming the cost to consumers would be negligible and the test itself could be carried out very quickly.
Alabama was the last state to enact an ignition interlock law, and it is still not mandatory for first-time DUI offenders unless they were arrested with a blood-alcohol content of 0.15 percent or higher, or if they refuse a breath test, had a child 14 or under in the vehicle or were involved in a crash. All repeat DUI offenders must have the device installed at their own expense in order for driving privileges to be restored.