Are Ignition Interlock Always Accurate?

In MA, any driver who has been granted a hardship license or is eligible for license reinstatement after an OUI is required to have an ignition interlock device (IID) installed in their vehicle. An IID is connected to your car’s ignition. To start the engine, you must first blow into the device, “passing” a breath test. If the IID registers any alcohol on your breath, the car will not start. The driver must also blow into the device periodically while operating the vehicle.

Many states now require IIDs under certain circumstances. In MA, you must have an IID installed in your vehicle if you are eligible for a hardship license after two or more convictions for OUI, and if you are eligible for reinstatement after two or more OUI convictions. In both cases, the IID must remain in your vehicle for at least two years. A MA OUI defense attorney can help you protect your rights if you’ve been charged with OUI.

Are IIDs Always Accurate?

An IID works much like a breathalyzer, which measures a person’s blood alcohol concentration (BAC) if stopped for OUI. IIDs work using either semi-conductors or fuel cell technology, although there is quite a bit of controversy over the accuracy of those that use semi-conductors. That being said, all IIDs can produce false positives.

Once the negative breath test is registered, the vehicle’s engine will start. However, the driver will be required to periodically pull over to perform another breath test in order to keep the vehicle moving. This is to prevent drivers from starting the vehicle sober and then opening a beer – or several – as they drive. If these periodic tests (called rolling tests) are not performed, your vehicle’s engine will shut off.

What is My IID Recording?

The IID also records information about your driving habits and test results. The IID will record anytime:

  • you have a measurable BAC,
  • you attempt to start the car without taking the test,
  • you refuse to take the rolling test,
  • you fail the rolling test, or
  • you tamper with or disconnect the IID,

as well as:

  • the distance your vehicle has traveled, and
  • the number of times you stopped or started your vehicle.

The Cost of an IID

Although total cost varies, installation and maintenance may set you back by up to $2,000 annually. Here is a general breakdown:

  • Installation: a minimum of $100
  • Monthly maintenance fee: up to $80
  • Monthly rental fee: up to $100

There are also additional fees for things such as obtaining restricted license classification and removing that classification once you have completed the program.

Participation in the IID program can be time consuming as well. You will need to schedule regular appointments during which the recorded information will be retrieved and the system will be recalibrated. And if your IID malfunctions or “locks up,” you will need to take it in for maintenance. A Boston OUI defense attorney can help you determine how to proceed if you’ve been charged with OUI.

Altman & Altman, LLP – OUI Defense Attorneys Serving Boston and the Surrounding Areas

If you have been charged with OUI or any other type of crime, the skilled legal team at Altman & Altman, LLP can help. We have been protecting the rights of individuals charged with criminal offenses for more than 50 years. Our experienced, knowledgeable attorneys have an impressive track record of getting clients’ charges reduced, or dismissed entirely. We understand that people make mistakes. Don’t make another one by hiring the wrong attorney. If you are facing charges for any type of crime, don’t attempt to handle things on your own. We can help. Contact Altman & Altman, LLP today for a free and confidential consultation about your case.


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