An alcohol ignition interlock device (IID) is a breath-test device that is connected to a vehicle’s ignition. A vehicle with an IID installed will not start unless the driver blows into the interlock and has a blood alcohol concentration (BAC) below a limit set by the court—usually .02 BAC. IIDs must be installed by a certified technician approved by the state’s department of motor vehicles (DMV). The IID will collect data (engine starts and stops, breath test results, and tampering attempts) and report it to the monitoring company, which will report it to the court.

IIDs reduce repeat offenses for DUI/DWI by approximately 70% when installed. Laws vary from state to state and courts have significant discretion, but a judge may order a person convicted of a first DUI/DWI offense to install an IID and will order a person convicted of a second or third DUI/DWI to install an IID. Courts will often order an IID installed on the defendant’s vehicle as a condition of bond (to be released from jail) and of probation (following jail or prison time, or in lieu of any or more jail or prison time). The court may order the defendant’s IID to remain on the vehicle for 1-3 years or more.

Despite these laws and programs, only about one-fifth of those arrested for DUI/DWI have an IID installed.

In North Dakota, the use of an alcohol ignition interlock device (IID) is a common legal requirement for individuals convicted of driving under the influence (DUI) or driving while intoxicated (DWI). State law mandates that any driver convicted of a DUI/DWI may be required to install an IID on their vehicle as part of their sentencing. This is particularly true for repeat offenders, where the court is more likely to order the installation of an IID. The device prevents the vehicle from starting if the driver's breath alcohol concentration (BAC) is above a preset limit, typically .02 BAC. Installation must be carried out by a certified technician approved by North Dakota's Department of Transportation (ND DOT), which is the equivalent of the DMV in some states. The IID records data such as engine starts and stops, breath test results, and any attempts at tampering, and this information is reported to the monitoring company and then to the court. The duration for which an IID must be installed can vary, but it typically ranges from one to three years, depending on the severity of the offense and the discretion of the court. Despite the effectiveness of IIDs in reducing repeat DUI/DWI offenses, compliance rates are not as high as the law intends, with a significant number of those arrested for DUI/DWI not having an IID installed.