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Alcohol and Drug Limits
- 1/27If your BAC is measured at 0.10%
The legal alcohol limit is 0.08%. Driving above this limit results in DUI charges, license suspension, and fines.
When driving under the influence of marijuana
DUI laws apply to drug impairment too. Legal or illegal, any substance impairing your ability can result in arrest.
While under 21 and BAC is detected at 0.02%
Idaho enforces zero tolerance for underage drinking. Any alcohol in drivers under 21 is punishable.
If you are a commercial driver with BAC of 0.05%
Commercial vehicle operators must stay under 0.04% BAC. Exceeding it results in suspension and job loss.
At a checkpoint, you refuse a breath test
Refusing chemical testing violates implied consent. Even without conviction, your license may be suspended.
If a crash occurs and you are found impaired
DUI resulting in injury or death is a felony. It leads to severe penalties including jail and long term suspension.
While on prescription medication that causes drowsiness
Driving under any impairing substance, including legal meds, is not allowed. It is treated like drugged driving.
When arrested for DUI with a child in the car
Idaho increases penalties for DUI with minors present. You may be charged with endangerment and face jail.
If you are caught driving drunk near a school zone
DUI in school or child safety zones leads to higher fines, more points, and extended suspension periods.
While driving high from cannabis edibles
Even if legally purchased, being high and driving is illegal. Delayed reactions and judgment make it dangerous.
When your first DUI conviction occurs
A first DUI usually results in license suspension, fines, and mandatory alcohol education classes.
If your second DUI happens within 5 years
Repeat offenses carry heavier consequences. A second DUI may include mandatory jail time and longer suspension.
When DUI arrest includes refusing field sobriety test
While you can refuse, it may be used against you. Officers may still arrest based on other observed impairment.
At the scene of a crash, officers smell alcohol
The smell of alcohol gives probable cause for testing. Refusal may result in immediate suspension or arrest.
If you are asleep in a parked car while drunk
Idaho may still charge DUI if you have control of the vehicle even if not driving while intoxicated.
When caught with illegal drugs in the vehicle
Possession alone may result in charges. If also impaired, it becomes a drugged DUI with heavier penalties.
If you fail both field and breath tests
Failing both tests gives strong evidence for prosecution. Penalties may include fines, jail, and license loss.
When under 18 and found driving under influence
Underage DUI leads to license revocation and delayed eligibility for reinstatement, plus education requirements.
While on DUI probation and caught drinking again
Drinking while on probation leads to arrest, longer suspension, and stricter monitoring.
When driving under combined influence of alcohol and drugs
Mixed impairment from alcohol and drugs results in tougher charges. This combination severely affects control.
If you test positive for illegal substances after a crash
Drug tests post crash may result in criminal charges. Even if the crash was not your fault, DUI laws still apply.
When convicted of DUI and fail to attend required course
Completing court ordered programs is mandatory. Skipping them delays or blocks license reinstatement.
If you drive after drinking 3 to 4 drinks in 1 hour
For most adults, this amount can exceed the 0.08% limit. BAC depends on weight, metabolism, and time.
At a DUI stop, you admit to using illegal drugs earlier
Confession leads to testing. If you are impaired, you’ll be charged regardless of how long ago you used.
While driving impaired near pedestrians or cyclists
Endangering vulnerable users while DUI raises charges. If injury occurs, you may be charged with a felony.
When DUI occurs with prior non DUI violations
Prior records, even if unrelated, can influence court sentencing. Judges may extend fines or suspension.
If a fatal crash results from DUI
DUI related deaths lead to the most severe legal outcome. Prison, felony charges, and permanent record apply.