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Interlock Devices and DUIs

If you were recently charged with a DUI, you might find yourself in need of an interlock device as a condition to get your license back or to receive a restricted license. If you’ve never seen or heard of an interlock device, read on to learn more about them.

What is an Interlock Device?

An ignition interlock device—also known as an IID—is essentially a breathalyzer for your car. An interlock device is connected directly to your car’s starter so that you cannot drive it if the interlock device detects that your BAC is above the acceptable limit.

How Does an Interlock Device Work?

First, an interlock device is an extremely sensitive breathalyzer device. When you breathe into it, alcohol in your breath causes a small amount of electric current to run through the sensor. The more alcohol in your breath, the higher the electrical current.

Second, the interlock device acts as a second ignition switch. If the BAC measured by the interlock device is within a predetermined limit, the device will then allow the ignition switch on your car to work, and you can then start it as you normally would. If your measured BAC is above the limit, then the device will not allow your car to start at all.

Third, an interlock device records information about your driving. This information is then regularly submitted and reviewed by the court or state DMV to make sure you’re complying with the terms of your interlock device program.

When Do You Need an Interlock Device?

Each state has its own requirements regarding who needs to install an interlock device and for how long. In the majority of states, interlock devices are mandatory for all DUI offenders. In other states, first-time offenders are not required to install interlock devices, but there are incentives for doing so. Check this list for specific requirements on interlock devices by state.

What are the acceptable BAC Levels for Interlock Devices?

While the federal BAC limit to drive is 0.08%, interlock devices are far stricter. Depending on your state requirements, your interlock device may register a violation if you test as low as 0.02%—essentially, after just one drink.

What Happens When You Fail an Interlock Device Test?

If you’re trying to start your car, then the interlock device will not allow you to start the ignition if your BAC is above the preset limit. The best next step is to sober up before you try starting your car again. Alternatively, you can arrange for a friend or cab to drive you home and pick up your car the next day.

Keep in mind that the interlock device logs each attempt to start the car and whether the attempt was successful. If it detects too many failed tests within a short period, the interlock device may completely lock down your car for 24 hours. If the interlock device locks down your car, then you won’t be able to start it again until the lockdown period is over, regardless of your BAC level!

How Often Do You Need to Use an Interlock Device?

An interlock device has to be physically connected to your car’s starter, so you need to use it each time before turning it on.

In addition, most states require random tests while your car is running. This is commonly known as a “rolling retest.” The purpose of a rolling retest is to ensure you don’t start drinking once you’ve started your car. Your interlock device will usually start beeping if it requires you to take a random rolling retest. You then have a few minutes to pull over your car to take the retest safely.

If you fail a rolling retest, it will not shut your car off automatically; however, the interlock device will record the violation, and you may face additional penalties later on.

Once you do shut off your car, you will always need to use the interlock device to turn it back on.

What if Someone Else Wants to Drive Your Car?

If someone else wants to drive your car, they need to also use the interlock device to start the car, even if they’ve never been involved in a DUI violation.

Remember that the BAC limit on the interlock device is much lower than the federal minimum. So, for example, if your friend’s BAC level is 0.03%, the interlock device will not allow the car to start, even if your friend would normally be legally allowed to drive with a BAC level of under 0.08%.

Under no circumstances should you allow someone else to take the interlock device test for you so that you can drive. This is a direct violation of your interlock device program.

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How Long Do You Need to Use an Interlock Device?

The exact time you’ll be required to install and use an interlock device on your car will depend on several factors, including:

  • The state where you committed the DUI violation
  • Your BAC level at the time of the DUI violation
  • Other circumstances of the DUI violation, for example, whether anyone was injured or killed
  • Your driving and DUI history

Depending on the circumstances, a first-time offender may need to install an interlock device for six months, while a repeat offender may need to use an interlock for as much as ten years.

What Information Does an Interlock Device Record?

Depending on the specific device and state requirements, your interlock device will record:

  • Your BAC level
  • When you start—or try to start—your car
  • When you shut off your car
  • Rolling retests and their results
  • Car location, mileage, and possibly GPS data
  • Photo and video to confirm who is using the interlock device
  • When someone attempts to tamper with or remove the interlock device

You will need to get your interlock device periodically calibrated, usually every month. When the interlock device is calibrated, all the data registered by the interlock device is downloaded and submitted to the DMV as required by state law.

How Much Does an Interlock Device Cost?

Since interlock devices are meant to be temporary, most people will lease an interlock device rather than buy one. It usually costs between $50 and $150 to install the interlock device. Once installed, most companies charge an additional $50 to $150 per month for monitoring and calibration.

What if You Don’t Want to or Can’t Use an Interlock Device?

Though interlock devices are a relatively inexpensive way to get back on the road safely, the costs may be out of reach for some. Some states offer financial assistance for those who can’t afford the cost of an interlock device, especially to those applying for a hardship license—that is, a special restricted license that allows you to drive to and from school or work. Many interlock device companies also offer payment plans if you’re unable to afford the upfront costs.

Unless you qualify for a very rare employer or medical exemption, then you will need to accept and install an interlock device if you want to keep driving.

Which Interlock Device Should You Install?

Check your state’s DMV site for a list of approved interlock device manufacturers and models. The largest interlock device manufacturers include Smart Start, Draeger, LifeSaver, and Alcohol Detection Systems.

What if You Don’t Own a Car?

If you get charged for a DUI violation if you’re driving a rental car or a borrowed car, you still need to follow your state’s interlock device requirements to drive legally. If, for instance, you want to drive a friend’s car again, your friend would need to install an interlock device in their car. Your friend would also need to blow into the device every time they wanted to drive, and they would also be subject to random rolling retests while driving.

If you decide to buy or lease a car of your own after your DUI charge, you will need to have an interlock device installed before you can drive it.

What Happens When You Violate the Terms of Your Interlock Device Program?

Violating the terms of your interlock device program include:

  • Failing to install an approved interlock device in your car
  • Driving any car without an approved interlock device installed
  • Failing a rolling retest
  • Being caught having another person use the interlock device so that you can drive
  • Tampering with or removing the interlock device
  • Failing to regularly service and calibrate the interlock device
  • Driving too far or driving anywhere other than work or school, as mandated by the court or DMV

If you’re in violation of your interlock device program, then you may be subject to some severe penalties, including:

  • Fines
  • Jail time
  • Revocation of your restricted license
  • Full loss of driving privileges until your full license suspension period is over
  • Having to drive with an interlock device for even longer
  • Violation of parole (if applicable)

Remember that driving with an interlock device is an alternative to having your license fully suspended revoked. If a court finds that you’re not taking the interlock device program seriously, it can always mandate that your license simply be suspended according to your original sentence.

SR-22 Adviser is committed to helping you get back on track. Our insurance partner can help you find the right insurance for your needs and budget, regardless of your driving record. You can get started online or over the phone at 877-822-2049.