DWI Vs. DUI: Comparing And Contrasting These Offenses (2025)

Laws Against Intoxicated Driving

Mood-altering substances, including alcohol, marijuana, illegal drugs, and prescription medication, can affect a user’s driving ability. Specifically, these substances can alter a person’s physical and mental faculties in the following ways:

• Slowed reflexes
• Loss of balance
• Impaired judgment and increased risk-taking
• Confusion and slowed thinking
• Inability to perceive distance or speed
• Emotional instability, including aggressiveness, paranoia, or anxiety

These effects significantly increase the driver’s risk of crashing. According to the National Highway Traffic Safety Administration (NHTSA), drivers with a 0.08% blood alcohol content (BAC) are four times more likely to crash than sober ones.

States know these statistics and have taken actions to prevent such dangerous behavior. Every state has a law against impaired driving. More importantly, every state has a law that drivers can violate in two ways.

Impaired Driving

First, these laws prohibit drivers from operating vehicles while their abilities are impaired by drugs or alcohol. A police officer can catch someone violating these rules when they see them driving unsafely. The following behaviors might signal to a law enforcement officer that a driver is impaired:

• Poor speed control, both speeding and driving too slowly
• Improper signaling
• Driving without headlights at night
• Poor directional control, including weaving or cutting corners
• Driving the wrong way
• Tailgating

In many cases, drunk driving violations are revealed after car accidents occur. If the officer determines the behavior resulted from alcohol or drug use, the driver can face criminal charges.

This violation applies regardless of the amount of intoxicating substance consumed. In other words, a conviction for these violations can rest solely on the officer’s testimony about the driver’s actions on the road.

Per Se Violations

As of 2004, every state prohibits driving with a blood alcohol content higher than a preset limit. All states set this limit at 0.08% BAC, with the exception of Utah, which has a legal limit of 0.05% BAC. Driving with a BAC over the limit is called a per se violation.

At this limit, the law presumes that the driver’s abilities are impaired. Based on scientific evidence, the majority of drivers experience difficulties with the following skills at 0.08% BAC:

• Focusing on driving
• Braking
• Steering
• Changing lanes
• Making decisions

However, to commit a per se violation, the offender’s driving does not need to exhibit impairment. The only evidence required to convict someone of a per se violation is a chemical test result giving a BAC over the state’s legal limit. Under implied consent laws, drivers suspected of DUI must submit to such tests or face penalties for refusal.

DWI vs. DUI: Punishing and Deterring Impaired Drivers

States use different terms for their drunk driving laws, including:

• Driving under the influence (DUI)
• Driving while impaired (DWI)
• Driving while intoxicated (DWI)
• Operating a vehicle while intoxicated (OWI)
• Operating a vehicle under the influence (OUI or OVI)
• Operating while ability-impaired (OWAI)

States pick one of these terms to cover the two driving violations involving drugs or alcohol. For example, Florida chose the term “DUI” for its offense, and it covers both impairment and per se violations.

A few states use multiple terms to describe different legal concepts involving drunk or high driving. For example, in some states, DUI and DWI are separate offenses. However, the difference between DUI and DWI depends on the state. Some of the ways states use DWI vs. DUI include the following:

Reduced Punishment

One state uses the difference between “under the influence” and “impaired” to impose separate punishments for the same crime. In Utah, prosecutors can bring a DUI charge for either an impairment violation or a per se violation.

However, the state’s laws allow prosecutors to reduce the charge to impaired driving in a plea agreement. The court can also lower the charge to impaired driving in the interests of justice.

So which is worse, DUI or DWI? DUI is much worse. A basic DUI offense is classified as a Class B misdemeanor, but prosecutors can raise it to a Class A misdemeanor if the driver had a minor passenger, was a repeat offender, or traveled the wrong way on the road. A DUI offender risks a punishment of six months to one year in jail.

DWI, by contrast, allows the judge to sentence the offender to probation and substance abuse treatment. This option is only available to first-time, low-level offenders who did not injure or kill anyone in a crash.

Age of the Driver

Some states use DUI and DWI to distinguish between adult and underage drinkers. For example, in Rhode Island, a driver of any age can commit a DUI by driving while their abilities are impaired or with a BAC of over 0.08%.

A DWI offense happens when a driver between 18 and 21 drives with a BAC of over 0.02%. In other words, DWI vs. DUI in Rhode Island imposes a lower BAC threshold on underage drivers.

Texas has a similar legal structure in which DWI is the general offense that drivers of any age can commit by driving while impaired or with a BAC of 0.08% or higher. DUI occurs when someone under 21 drives with any detectable amount of alcohol in their system.

Level of Impairment

Colorado uses DUI and DWAI to describe two separate offenses that a driver of any age can violate. In other words, unlike in Texas and Rhode Island, adults and minors alike can face either a DUI or DWAI charge.

What does DUI stand for in Colorado? This charge means the driver was substantially incapable of safely operating a vehicle. What does DWI stand for in Colorado? Prosecutors can bring this charge anytime an officer witnesses a driver affected “to the slightest degree” by drugs or alcohol.

Contact ConsumerShield to Learn More

Regardless of the term your state uses, drunk driving charges can happen whenever a police officer believes drugs or alcohol have affected your driving abilities. Defending against these charges can require a detailed understanding of your state’s criminal laws and procedures. Contact us for a free case review and a referral to a DUI lawyer to help you.