DUI Under 21 in Idaho:
Zero Tolerance & License Consequences

DUI Under 21 in Idaho: Zero Tolerance & License Consequences

In Idaho, the legal drinking age is 21, but you can get your driver’s license at the age of 15. While it’s unlawful to drive under the influence of alcohol at any age, it is especially problematic for underage drivers; drivers under 21 are held to a much stricter standard than adults, and even a small amount of alcohol—less than the legal limit for adults—can lead to a serious Driving Under the Influence (DUI) charge.

Sullivan Law Office in Coeur d’Alene, Idaho, represents clients in North Idaho accused of all crimes, including vehicle-related crimes. DUIs are not traffic infractions like a ticket for speeding or running a red light; DUI is a criminal offense. If you or your child is dealing with an underage DUI in Idaho, here’s what you need to know about the law, possible penalties, and how a conviction can affect your child’s future.

Idaho’s Zero-Tolerance Standard for Underage DUI

Idaho’s zero-tolerance law makes it clear: if you’re under 21 and caught driving with alcohol in your system, you face immediate and long-term consequences. Under Idaho Code §18-8004(1)(d), drivers under 21 can be charged with DUI if they have a BAC of 0.02% or higher. This threshold is far lower than the 0.08% limit for adults.

A BAC of 0.02% can result from one drink or even less, depending on the person’s weight, metabolism, and how quickly they consumed the alcohol. In many cases, teens are surprised to learn how little it takes to trigger a DUI charge. Getting pulled over for even a small traffic infraction can lead to big trouble if a law enforcement officer (LEO) suspects a DUI.

During a traffic stop, an officer may investigate underage DUI if they notice:

• The smell of alcohol
• Slurred speech or glassy eyes
• Open containers in the vehicle
• Poor performance on field sobriety tests
• Admission of drinking—even a single sip

It can happen more easily than you think. It’s nerve-racking enough to get pulled over, especially if you are a teen. Even if it’s just anxiety, an officer may conclude that there is probable cause to investigate further. If there is any evidence of alcohol, the LEO can arrest the driver and request a breath or blood test. Because of Idaho’s implied consent law, refusing a chemical test triggers serious license consequences.

Refusal to Take a Chemical Test

As with all drivers, if an underage driver refuses a breath, blood, or urine test, Idaho’s implied consent rules impose mandatory penalties:

• One-year license suspension for a first refusal
• Two-year suspension for a second refusal

These penalties may apply even if the DUI charge is later reduced or dismissed. Idaho’s implied consent rule holds that driving on Idaho roads constitutes consent to undergo a chemical test when requested to do so by an LEO. Because of this rule, refusing a chemical test is a separate case with its own penalties.

This suspension is not automatic. If you refused an evidentiary test, you have the right to request a hearing to contest the suspension. If you hire Sullivan Law, a request to contest the suspension must be filed quickly — you only have seven days.

Penalties for an Underage DUI Conviction

Even though an under-21 DUI is treated differently from an adult DUI, the consequences are still serious and can disrupt school, work, and future opportunities.

First Offense

• 1 year license suspension
• Mandatory Substance Use Evaluation
• Fines up to $1,000
• Possible community service
• Possible ignition interlock requirement

Second or Subsequent Offense

• Mandatory minimum 5 days jail, with a maximum of 30 days
• Longer license suspensions
• Greater fines
• Ignition interlock requirements
• Higher likelihood of probation
• Increased scrutiny from schools, employers, and licensing boards

Even a first offense creates a permanent criminal record, which can affect scholarships, sports eligibility, employment, and college admissions.

Can an Underage DUI Become an Adult DUI?

Yes. If a driver under 21 has a BAC of 0.08% or higher, Idaho treats the case as a standard adult DUI, with harsher penalties, potential jail time, and higher fines. Additionally, if drugs (whether prescription or illicit) are involved, the state may pursue adult DUI charges regardless of age.

Long-Term Consequences for Minors

Even just one underage DUI can follow a young person for years. Common consequences include:

• Higher insurance costs or cancellation of coverage
• Barriers to military enlistment
• Problems with professional licensing later on
• School disciplinary actions
• Loss of job, college, or internship opportunities

Because young adults are just beginning to build their future, protecting their records is critical. A DUI conviction can be life-altering.

How an Attorney Can Help

Underage DUI cases require careful handling. An experienced Idaho DUI attorney can build a defense case that can improve a minor’s chance of avoiding or minimizing the lifetime consequences of a conviction. For example, an attorney can:

• Evaluate whether police had lawful grounds for the stop
• Challenge BAC results and testing procedures
• Seek reduced charges or diversion options
• Protect educational and career opportunities
• Fight to preserve driving privileges
• Move the proceeding to juvenile court

The earlier an experienced attorney gets involved in the case, the greater the opportunity to improve the outcome. Importantly, if you are faced with an underage DUI, do not say or do anything until you have spoken with your attorney, or you may forfeit important rights.

If your child or loved one is facing an underage DUI in Idaho, contact Sullivan Law Office, PLLC immediately. We work to protect young drivers’ rights and futures, and we fight to prevent one mistake or poor decision from defining the rest of their lives.

This provides general information and is not legal advice for any specific individual or case.