Interlock Devices Reduce Repeat DUI Offenses

One of the strongest arguments for interlock programs is their impact on recidivism—the rate at which someone is arrested again for impaired driving.

Key reasons:

• The device physically stops the car from starting if alcohol is detected.

• This removes the “impulsive decision” factor that often leads to repeat DUIs.

• States with aggressive IID programs consistently report lower reoffence rates.

While the device is installed, re-arrest rates drop dramatically because impaired driving simply becomes impossible.

Interlocks Increase Public Safety

Courts and DMVs view IIDs as a way to protect:

• Other drivers

• Pedestrians

• Families

• Communities

Unlike license suspension alone, an IID ensures the individual cannot operate a vehicle while impaired, even if they attempt to drive illegally.

This is one of the main reasons policymakers prefer IIDs over long-term license suspensions.

IIDs Provide Verifiable Data for Compliance

Courts and DMVs rely on interlock data because it creates a transparent record of driver behavior.

IIDs automatically record:

• Passed and failed breath tests

• Missed rolling retests

• Attempted tampering

• Power loss events

• Lockouts

• Exact dates and times of all activity

This data helps courts:

• Verify sobriety

• Enforce laws consistently

• Identify patterns of risk

• Support early reinstatement when appropriate

Without an IID, none of this information would exist.

States Tie License Reinstatement to Interlock Compliance

Many states now make IIDs a direct requirement for:

• Restoring driving privileges

• Completing a DUI program

• Ending a suspension

• Transitioning from a hardship license to a full license

In these states, failing to complete the IID program successfully means you cannot get your license back.

Interlocks provide a structured path to regaining driving privileges safely.

Common Situations Where an IID Is Required

Although every state has its own laws, the most common triggers include:

1. First-Offense DUI with High BAC

If the BAC is above a threshold (commonly 0.15+), an IID is often mandatory.

2. Repeat DUI Offenses

Multiple DUI convictions almost always result in interlock installation.

3. Chemical Test Refusal

Refusing a breath or blood test during a traffic stop can automatically trigger an IID requirement in many states.

4. Hardship or Restricted Licenses

Drivers may be allowed to travel to work, school, or treatment programs—but only with an IID installed.

Why Courts Prefer IIDs Over Full License Suspensions

A suspended license does not always stop impaired driving. Many drivers simply drive illegally.

An IID, however:

• Ensures the car cannot start if alcohol is present

• Allows offenders to legally maintain employment

• Encourages treatment compliance

• Reduces financial strain from totally losing transportation

This balance of accountability and practicality is why interlocks have been adopted nationwide.