Interlock devices are breath test kits that you use to start your car. When an interlock device is installed in your car, you need to blow into the machine to prove that you have not been drinking. It will not start if it detects alcohol.
Historically they've been required for repeat DUI offenders and special cases of extreme intoxication. One recent study at Johns Hopkins Bloomberg School of Public Health has found that they reduce traffic deaths, which is likely to increase the push for their use on a larger scale, both nationally and in Pennsylvania.
The Johns Hopkins study
While interlock devices have been in regular use since the 1980s, the study tracks auto fatalities through the year 2013. The study concludes that deaths have decreased by 7 percent in states where first time DUI offenders use them, as compared to states that only sentence the machines to repeat offenders.
Interlocks in Pennsylvania
Today, 22 different states require an interlock device for first-time offenders, though Pennsylvania is not among them. Here, drivers are required to use the breath test-ignition lock on second offense for driving while intoxicated. However, for anyone who registers between .10 to .15 BAC on first offense, their license will not be suspended if they agree to drive using the device for one year.
Whenever the flashing lights come on in your rearview, there is a "gotcha" feeling, even if the driver is innocent of a crime. Even drunk driving charges are fallible, as breathalyzers and sobriety tests are subject to human and mechanical error just like anything else.
An arrest is not a conviction, and there are legal arguments for those who are wrongfully accused. For those who have made the mistake of driving under the influence, considering an interlock device may reduce the punishment and ensure that you don't make the same mistake twice.