What is DUI & DWI Law?

Criminal charges and the tests officers use

By Super Lawyers staff | Reviewed by Canaan Suitt, J.D. | Last updated on July 10, 2023 Featuring practical insights from contributing attorney Ben Sessions

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Drivers who operate a motor vehicle under the influence of alcohol or drugs threaten the safety of other motorists and pedestrians and risk being charged with a DUI (driving under the influence) or DWI (driving while intoxicated).

While different in name depending on your state, DUI/DWI charges follow similar procedures. They can range in severity from a misdemeanor to a felony depending on factors such as your blood alcohol concentration (BAC) and whether it was a first offense. Punishments for driving under the influence can include revocation or suspension of your driver’s license, community service, fines, and jail time.

If you’ve been charged with a DUI, it may be your first experience with the criminal justice system. It’s natural to feel overwhelmed in the process, and uncertainty can kick in as soon as you’re pulled over by a law enforcement officer. For example, you may be unsure whether you can challenge any of the intoxication tests you were asked to complete.

The following is designed to give you an overview of DUI/DWI charges and the tests officers use, so you feel confident speaking with a lawyer. As Ben Sessions, a DUI lawyer at Sessions & Fleischman in Atlanta says, “A DUI lawyer aims to help people who have been charged with a DUI offense navigate the legal process and hopefully mitigate the punishments as much as possible.”

Understanding DUI/DWI Charges

DUI/DWI laws are criminal laws created at the state level that make it illegal to operate a vehicle while impaired by alcohol or mind-altering drugs.

Sessions explains that in the state of Georgia, for example, “There are six different ways that you can be charged with a DUI, and you can be charged with all six types of DUI charges at one time They all involve some allegation of alcohol and/or drug use, or in some rare cases, toxic vapors.”

DUI laws vary from state to state, but they generally fall into two categories:

DUI Per Se Laws

Every state has set a limit at which you are considered legally intoxicated, even if you aren’t exhibiting signs of intoxication. This is usually referred to as “the legal limit” and is most commonly a blood alcohol content (BAC) of .08%.

The legal limit may be lower for other types of drivers. For example, in Georgia, the limit is .02% for non-commercial drivers under 21 and .04% for drivers with a commercial driver’s license (such as truck drivers).

DUI per se violations are relatively easy for prosecutors since they simply have to prove that you were over the legal limit regardless of actual impairment.

We charged people with being intoxicated drivers long before we ever had a machine that a person could sit in front of to tell what their BAC was. And we did that by virtue of looking at a person to see how they talked, walked, drove—all those sorts of cumulative factors to determine whether or not the person was affected by alcohol.

Ben Sessions

DUI Impairment Laws

Unlike DUI per se charges, DUI impairment charges aren’t connected to a specific BAC limit. “These charges just mean that you’re an impaired driver as a result of alcohol,” explains Sessions. “It could be to any extent.”

So, if your BAC level was .03 but you were swerving and unable to control the car due to intoxication, you can be charged with a DUI regardless of the fact that you were well below the legal limit.

“Think about it in these terms—there were DUI charges well before we had breath test machines,” says Sessions. “We charged people with being intoxicated drivers long before we ever had a machine that a person could sit in front of to tell what their BAC was. And we did that by virtue of looking at a person to see how they talked, walked, drove—all those sorts of cumulative factors to determine whether or not the person was affected by alcohol.”

Proving impairment isn’t necessarily as straightforward as proving a DUI per se. Prosecutors will draw on several types of evidence to try to establish beyond reasonable doubt that you were impaired when driving the car. Evidence might include field sobriety test results, witness testimony, or video footage.

Testing for Intoxication

If you are stopped by an officer who suspects you may be drunk driving, the officer might ask you to complete some field sobriety tests.

The general field sobriety test includes the horizontal gaze nystagmus, the walk-and-turn, and the one-leg stand.

Horizontal Gaze Nystagmus

During this test, the officer will have you follow a pen with your eyes, and they will look for any involuntary eye movement (called nystagmus).

Nystagmus is the repetitive and uncontrolled jerking of the eyes, and it is usually more pronounced when a person is intoxicated. During this test, the officer notes the angle at which a person’s eye bounces or jerks.

Walk-and-Turn Test

This test has two parts: the instruction and the performance.

During the instruction, you will be asked to stand heel to toe and listen while the officer explains what you will do next. After the instruction, you will take heel-to-toe steps forward, turn around and walk back to your starting point.

The officer will be looking for signs you may be intoxicated, such as taking the wrong number of steps, starting too soon, or stepping off the line.

One-Leg Stand

During this test, you will be asked to stand with one leg slightly off the ground while counting until you are asked to put your foot down.

Usually, you will be asked to balance for about 30 seconds with your eyes on your elevated foot and your arms at your side. The officer will be looking for signs of intoxication, such as swaying, hopping, or putting your foot down.

These tests are all standardized, which means the officer should follow specific guidelines when administering the tests. The accuracy of the field sobriety test is highly dependent on varying factors, including whether they were administered correctly.

Chemical Tests: Breath and Blood Alcohol Tests

A police officer might also ask you to submit to a breathalyzer test, which measures the amount of alcohol on your breath. In some cases, you may be asked to submit to a blood alcohol level test or urine test. These tests are generally not done on the side of the road, and each state has its own requirements for who can administer the tests and how they are analyzed.

“I know there are a lot of lawyers who unequivocally say to people, ‘You should always refuse to submit to a test after arrest,’” says Sessions. “That’s an easy middle-of-the-way answer to give. But I don’t think that question is so easily answered. For example, if it’s really true that someone who weighs 170-180 pounds only had one beer, there’s almost no way they’re going to be above the legal limit of .08. At any rate, I don’t tend to give those sort of categorical answers. I believe you should make that decision on a case-by-case basis.”

It’s very important to note that under implied consent laws, drivers may face serious consequences for refusing a test. Every state has implied consent laws, which say that by driving, you have consented to chemical or field sobriety testing if a police officer reasonably suspects intoxication.

The penalties for refusing to submit to testing vary by state. They can include driver’s license suspension, fines, and even jail time. So, it’s important to know what the consequences of refusing a test are when making that decision. Some states allow you to speak with a lawyer before deciding whether to submit to a test, and you may want to consider whether that is an option for you.

Consequences of DUI/DWI Charges

Penalties for driving while intoxicated vary by state. You might face enhanced penalties if there was a child in the car, if an accident or injury resulted from your intoxicated driving, or if you have a prior DUI offense.

Common penalties include:

  • Fines
  • Driver’s license suspension
  • Jail time (especially if you already have a second offense on your record)
  • Mandatory alcohol education or treatment programs
  • Ignition interlock devices

An ignition interlock device can be installed in your vehicle that includes a breathalyzer with a pre-set blood alcohol content limit. Your car will start if the breath test results are below the pre-set limit. If not, you will not be permitted to drive. Some jurisdictions require the installation of an interlock device after a specified number of DUI convictions.

“Whenever people are arrested with a DUI, they rarely consider the consequences beyond the actual arrest,” says Sessions. But individuals who are charged with a DUI will immediately be confronted with practical questions such as:

  • What’s going to happen to my job in the interim as a result of an arrest?
  • What’s going to happen to my job in the long term if I’m ultimately convicted of the DUI?
  • Can I plead it to a lesser offense and save my job?
  • What happens if I can’t travel in connection with my job because my driver’s license has been suspended?

Sessions recommends that individuals immediately consult their employee handbook to see what their employer requires as far as reporting an arrest. He urges clients to be transparent rather than try to conceal a DUI. Misrepresenting what happened will only create more problems. And he often recommends that clients engage in some form of substance abuse evaluation to demonstrate commitment to addressing the issue.

He adds that if you have any professional licensing, you should also check to see if your licensing authority requires disclosure of an arrest. You don’t want to risk losing licensure through failure to report.

What to Do if You’ve Been Charged With DUI/DWI

DUI cases proceed through the legal system like most other cases in the criminal justice system.

If you’re charged with a DUI, you will need to be booked and informed of your charges. You’ve probably heard the famous Miranda rights in movies or television shows, and it’s important to take those seriously: You do have the right to an attorney, and you have the right to remain silent when being questioned in police custody. Many attorneys recommend that you only speak to law enforcement with an attorney present so as to avoid incriminating statements or admitting guilt.

It’s important to contact a DUI attorney as soon as possible for legal representation. If you cannot afford an attorney, you can request that the court appoint one for you.

You will then go before a judge to enter your plea. You or your lawyer may file suppression motions to challenge the admission of any field sobriety tests you were asked to take. If these challenges are successful, it could result in your case being dismissed.

It is rare for a DWI case to go all the way to trial. Most defendants plead to a lesser charge, such as reckless driving, or come to an agreement with the prosecutor.

To me, the value of having a lawyer who specializes in the nuances of DUI cases is to be able to navigate the administrative process a lot more smoothly, understand what’s going on with the legal process, and know what your risks are and aren’t. Another benefit of DUI expertise is understanding the admissibility of various types of tests.

Ben Sessions

Defenses and Legal Strategies for DUI/DWI Charges

Every DUI case is different, and legal strategy must take account of your particular circumstances and state laws. That being said, common defenses to a DUI include:

  • Challenging the legality of the traffic stop
  • Showing that you weren’t operating the vehicle
  • Disputing the results of the tests that were used to measure intoxication

Depending on the facts of your case, you may be able to successfully negotiate a plea deal resulting in reduced charges or an alternative sentencing program.

Working with an Experienced DUI Defense Attorney

If you’re facing criminal charges for driving while intoxicated, it’s wise to consult an attorney as soon as possible. What kind of lawyer do you need?

“To me, the value of having a lawyer who specializes in the nuances of DUI cases is to be able to navigate the administrative process a lot more smoothly, understand what’s going on with the legal process, and know what your risks are and aren’t,” says Sessions. “Another benefit of DUI expertise is understanding the admissibility of various types of tests,” he adds.

“But let’s say I’ve got a run-of-the-mill DUI where a person was stopped for speeding,” continues Sessions. ”There’s no quirky issue as it relates to the admissibility of a field sobriety test or other evidence. The person is arrested for a DUI and they refuse to submit to a breath test. My personal perspective is that sort of case can be effectively handled by any competent, hard-working criminal defense lawyer. DUI lawyers who deal with these cases more frequently might be able to present the evidence in a better way, but those cases are truly not magic.”

Common Questions for an Attorney

Below are some common questions you might want to consider when meeting with an attorney for the first time.

Can a DUI or DWI attorney help me avoid jail time?

A DUI defense attorney’s goal is to help mitigate the consequences of your DUI/DWI as much as possible. The penalties you face for a DUI depend on the circumstances of your case. An attorney won’t be able to make specific promises as to the outcome, but they can let you know what seems likely based on their experience and keep you informed of your options at every step of the process.

Will I have to go to trial for my DUI or DWI case?

Many DUI cases are resolved before going to trial. Whether you go to trial or settle beforehand will depend on several factors, including what your attorney thinks is the best legal strategy based on your situation.

Will a DUI affect employment?

A DUI has the potential to negatively impact your employment in various ways. As a general rule, you want to make sure you are following your employer’s requirements around reporting an arrest. It’s wise to consult with an attorney to see if there are any further steps you can take to mitigate the employment-related fallout of a DUI.

How can I prepare for an initial consultation with a DUI or DWI attorney?

Be prepared to answer the attorney’s questions about your DUI honestly and as thoroughly as you can. If you have any documentation related to the arrest or charges, bring those. Think about any questions or concerns you have, including the questions listed here, and maybe write them down so you’re sure to remember and get them addressed.

Will the attorney handle all aspects of my DUI or DWI case, including administrative hearings and court appearances?

Yes, generally speaking, a DUI attorney will handle all the legal aspects of your DUI case. That includes keeping you informed about what you need to do as far as court dates and appearances.

Finding the Right Attorney for Your Needs

Criminal law is a challenging legal area where results can have lasting implications. It’s essential to find the right attorney—someone you feel confident in and who can help you through your entire case. To do so, visit the Super Lawyers directory and search for a criminal defense lawyer specializing in DUI/DWI law.

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