Ignition Interlock Device Laws in California

In the ongoing battle against drunk driving, California has implemented a robust system of measures to protect road users. One key tool in this fight is the ignition interlock device (IID), a machine that aims to prevent intoxicated individuals from operating a vehicle. In this article, we will delve into the specifics of IID usage in California, answering crucial questions about installation, duration of use, and the consequences of tampering.

When are Ignition Interlock Devices Used in California?

First and foremost, when are ignition interlock devices installed on vehicles in California? The answer lies in the legal framework established by the state. IIDs are primarily required for individuals convicted of driving under the influence (DUI) offenses. Specifically, anyone convicted of a DUI in California will be mandated to install an IID in their vehicle, especially for repeat offenders or those with high blood alcohol concentrations (BAC). Additionally, individuals who have their driving privileges reinstated following a license suspension may also be subject to IID installation.

How Long Are Ignition Interlock Devices Installed in California?

The duration of IID usage varies depending on the circumstances of the offense. For first-time DUI offenders, the installation period typically ranges from 4 to 6 months. However, for subsequent DUI convictions, the requirement may extend to 1 to 3 years or even longer. It is important to note that the actual installation and monitoring of the IID are administered by state-approved service providers. Offenders are responsible for covering the costs associated with device installation, calibration, and maintenance.

Tampering with an Ignition Interlock Device in California

Now, let’s address the consequences of tampering with an ignition interlock device. Tampering with or attempting to bypass the IID is a serious offense in California. It is a violation of the law and can lead to severe penalties. The California Vehicle Code specifically prohibits tampering with an IID, which includes any actions aimed at circumventing, disabling, or manipulating the device’s functionality. Consequences for tampering may include an extension of the IID requirement, an extension of the overall probation period, and even additional criminal charges.

“Tampering” can include having another person blow into the device in order to manipulate its results, removing the device from your vehicle altogether, or driving a vehicle registered to another driver in order to bypass the IID altogether.

It is crucial for individuals to understand the gravity of tampering with an IID. The device is specifically designed to ensure road safety by preventing intoxicated individuals from operating a vehicle. Any attempt to tamper with or subvert its purpose poses a significant risk to public safety and undermines the intent of the legal measures in place.


To put it all together, here is what you need to know about Ignition Interlock Devices in the state of California:

  • IID’s are primarily installed as a result of a DUI charge.
  • First time offenders of DUI will have to install an IID in the vehicle without exception.
  • Offenders will have an IID installed on their vehicle between 4 to 6 months, but subsequent offenses will extend that duration, which can last 1 to 3 years, or even longer.
  • Tampering with an IID is a serious offense that will lead to substantial criminal penalties, such as hefty fines, an extended IID installation period, and even jail time.

Putting it all Together

Ignition interlock devices play a vital role in curbing the incidence of drunk driving in California. Their installation is typically required for individuals convicted of DUI offenses, serving as a preventive measure to safeguard against repeat offenses. The duration of IID usage varies based on the nature of the offense, ranging from several months to several years. Tampering with an IID carries severe consequences, including extended IID requirements, prolonged probation, and potential criminal charges. By adhering to the regulations surrounding IIDs, drivers can contribute to a safer road environment while working towards their own rehabilitation and the prevention of further DUI incidents.

If you or a loved one has been charged with driving under the influence and you believe that you were falsely arrested, then use our free consultation form at the top of the screen for a confidential, no-obligation consultation with a DUI/DWI attorney or call us at (800) 384-5297.