What happens when California suspends your license for a DUI
California suspends your driver's license in two separate ways after a DUI arrest. The first suspension comes from the Department of Motor Vehicles (DMV) based on the arrest itself — this is called an administrative suspension and happens whether or not you're convicted. The second suspension comes from the court if you're convicted of DUI — this is called a court-ordered suspension. The DMV suspension typically lasts four months for a first offense, while the court suspension lasts six months.
An interlock device is a breath-testing machine installed in your vehicle that prevents the engine from starting if it detects alcohol on your breath. California requires this device for certain drivers, but the timing and rules depend on which suspension you're under and what stage of the process you're in. Understanding which suspension applies to you right now determines what you can and cannot do with your vehicle.
Key Takeaways
- California's DMV suspension (administrative) and court suspension (court-ordered) are separate, and you may be under one, both, or neither depending on your case status.
- An interlock device lets you drive during a suspension if you install it, but you must have a restricted license from the DMV first — you cannot straightforward install one and drive.
- The DMV offers a restricted license after four months of the administrative suspension if you install an interlock device, but you must request it and meet other requirements.
- If you're convicted in court, the judge decides whether an interlock device is mandatory, optional, or not required as part of your sentence.
- Interlock devices cost between $60 and $150 per month to lease and maintain, and you pay this cost yourself.
The DMV administrative suspension and interlock option
When you're arrested for DUI in California, the officer takes your physical license on the spot. The DMV then sends you a notice of suspension that takes effect 30 days after your arrest. This is the administrative suspension, and it lasts four months for a first offense (longer for repeat offenses). During these four months, you cannot legally drive — period — unless you obtain a restricted license.
After you've served at least four months of this suspension, the DMV will issue you a restricted license if you meet three conditions: you install an interlock device in your vehicle, you pay the DMV's reissuance fee (currently $125), and you provide proof of financial responsibility (usually an SR-22 insurance form). With this restricted license and the interlock device installed, you can drive to work, school, medical appointments, and alcohol treatment programs — but nowhere else. The device records every breath test, and those records go to the DMV.
You do not have to wait the full four months if you request a stay of suspension or fight the suspension through the DMV's administrative hearing process. If you win the hearing, the suspension is cancelled. If you lose, you still serve the four months, but you may have bought time to prepare for the interlock installation or other requirements.
The court-ordered suspension and interlock requirements
If you're convicted of DUI in criminal court, the judge imposes a separate suspension on top of the DMV's administrative one. For a first DUI conviction, the court suspension is typically six months. However, the judge has discretion to reduce this to three months if you install an interlock device. This is different from the DMV's rule — the court can make the interlock device a condition of reducing your suspension time.
The judge's order will specify whether the interlock device is mandatory, optional, or not required. If it's mandatory, you must install it before you can drive on a restricted license. If it's optional, you can choose to install it to shorten your suspension, or you can serve the full suspension without one. Read your court documents carefully, because the judge's exact language determines your options.
Unlike the DMV's restricted license, which has specific permitted purposes, a court-ordered restricted license with an interlock device usually allows you to drive for any lawful purpose — work, errands, appointments — as long as the device is installed and functioning. However, you still cannot drive with any measurable alcohol in your system, because the interlock will not start the vehicle.
How the interlock device actually works
An interlock device is a small breathalyzer connected to your vehicle's ignition system. Before you start the engine, you blow into the device. If your breath alcohol content is below the legal threshold (typically 0.02% for interlock purposes, lower than the 0.08% DUI limit), the device allows the engine to start. If your breath alcohol is above the threshold, the engine will not start, and the device records the failed attempt.
While you're driving, the device may ask for a rolling retest — a breath test at random intervals after the engine is already running. This prevents you from having someone else blow into the device to start the car and then drinking while driving. If you fail a rolling retest, the device logs the violation and may trigger your vehicle's lights and horn as a warning.
You must visit a certified interlock service provider every 30 days for device maintenance and data read. The service provider reads the device's records and sends a report to the DMV or court. If the report shows multiple failed tests or tampering attempts, the DMV or court may extend your suspension or revoke your restricted license. The cost of installation, monthly leasing, and maintenance typically runs $60 to $150 per month, and you pay this yourself.
When you're under both suspensions at the same time
Most DUI cases involve both the DMV administrative suspension and a court-ordered suspension running at the same time. The suspensions do not stack — meaning you do not serve them one after the other. Instead, they run concurrently, and whichever one lasts longer controls when you can drive again.
For example, if the DMV suspends you for four months and the court suspends you for six months, you cannot legally drive until the court's six-month suspension ends — even though the DMV's four months are up. However, if you install an interlock device, the DMV will issue you a restricted license after four months, allowing you to drive with the device. The court's suspension still runs in the background, but the restricted license lets you drive during that time as long as the interlock is installed.
This overlap creates confusion because you may be may be able to access for a DMV restricted license before the court suspension ends. The key is that both the DMV and the court must agree you can drive. If either one says no, you cannot drive, even if the other says yes. Always check both your DMV notice and your court documents to understand which suspension is currently in effect.
What disqualifies you from using an interlock device
California law does not allow everyone to use an interlock device as a way around suspension. If you have two or more DUI convictions within ten years, you are required to install an interlock device — it is not optional. However, if you have three or more DUI convictions within ten years, you face a mandatory license revocation, and an interlock device does not restore your driving privileges. You must wait out the full revocation period and then go through the DMV's reinstatement process.
Additionally, if you refuse to take a breath or blood test after a DUI arrest, the DMV's administrative suspension is longer (one year instead of four months), and the interlock option may not be available during the first part of that suspension. The exact rules depend on whether this is your first refusal or a repeat refusal.
If the court finds that you tampered with an interlock device, drove a vehicle without one when required, or failed multiple breath tests, the court can revoke your restricted license and extend your suspension. Tampering includes having someone else blow into the device, disconnecting it, or attempting to bypass it in any way.
Steps to get a restricted license with an interlock device
First, determine which suspension you are currently under by checking your DMV notice and your court documents. If you are under the DMV administrative suspension, wait until you have served at least four months from the suspension start date. If you are under a court-ordered suspension, check whether the judge made the interlock device mandatory, optional, or not required.
Second, contact a certified interlock service provider in California. The DMV maintains a list of approved providers on its website. Call the provider and schedule an installation appointment. Bring your driver's license (even though it is suspended) and proof of vehicle ownership or registration. The installation takes about one hour. You will receive a receipt and installation documentation.
Third, submit your interlock installation documentation to the DMV along with the restricted license request form (DL 44 or DL 44D, depending on your situation) and proof of financial responsibility (SR-22 form from your insurance company). You can submit these by mail or in person at a DMV office. Include the DMV reissuance fee ($125 as of 2024, though this may change). The DMV will process your request and mail you a restricted license within two to three weeks.
Fourth, once you receive your restricted license, you can legally drive only for the purposes listed on the license (work, school, medical, treatment) if you have a DMV restricted license, or for any lawful purpose if you have a court-ordered restricted license with interlock. Keep your restricted license, proof of interlock installation, and your vehicle registration with you at all times while driving. If you are stopped by police, show all three documents.
Frequently Asked Questions
Can I drive to the interlock service provider's office if I do not have a restricted license yet?
No. You cannot legally drive to the appointment to install the interlock device unless you already have a restricted license. You must arrange a ride from someone else, use a taxi or rideshare service, or have the provider pick you up. Some providers offer mobile installation at your home or workplace, which avoids this problem.
What happens if the interlock device malfunctions or I cannot afford the monthly fee?
If the device malfunctions, contact your service provider when ready and request a replacement. The provider must install a working device within a set timeframe, usually 24 to 48 hours. If you cannot afford the monthly fee, you can request a hardship exemption from the DMV, but this is rarely granted. If you stop paying and the device is removed, your restricted license is automatically revoked and your suspension resumes.
Do I have to install an interlock device if the judge did not order it?
If the judge made the interlock device optional and you choose not to install one, you must serve the full court suspension without driving. However, if you are also under the DMV administrative suspension, you cannot get a DMV restricted license without installing the device. Your options depend on which suspension is longer and what the judge's order says.
Can I remove the interlock device early if my suspension ends?
Yes, but only after both your DMV suspension and your court suspension have ended. Once both are complete, contact your interlock service provider and request removal. The provider will remove the device and send a final report to the DMV and court. You must pay any remaining monthly fees before removal. After removal, you can drive normally without the device.
What if I move out of state while my interlock requirement is active?
California's interlock requirement follows you if you move to another state, because it is tied to your California driver's license. You must maintain the interlock device in your vehicle and continue monthly service visits until your California suspension ends. If you move to a state that does not have certified interlock providers, contact the DMV to discuss your options — you may be able to request a modification of your requirement.