In every state, you can get a DUI for driving while impaired by drugs or alcohol. And even if you aren't technically impaired, you can be convicted of a "per se" DUI for operating a vehicle with a blood alcohol concentration (BAC) of .08% or more.
The consequences of a DUI are always serious, even for a first offense. But the penalties are further enhanced for second-offense DUIs.
What counts as a second DUI differs by state, and the criteria aren't always obvious. Just because you have a prior DUI conviction doesn't necessarily mean your next offense will count as a second DUI. On the other hand, some states allow you to be convicted of a second DUI even when you don't technically have a first DUI conviction on your record.
In some states, such as California, a second DUI counts as a second offense only if it occurred within a certain period of time of the first offense. This period is sometimes called the DUI "lookback" period. For instance, some states count a DUI as a second offense only if it occurred within 10 years (the lookback period) of a first DUI. In these states, a 12-year-old DUI conviction wouldn't count against you as a prior offense.
Other states, like Indiana, don't have a lookback period. In these states, a DUI counts as a prior forever: A second DUI will be considered a second offense regardless of how long ago the first happened.
A prior DUI conviction from another state might not count when totaling the number of offenses. In states that don't count DUIs from other states, someone with a prior DUI conviction from another state will be considered a first-time offender for purposes of a new case.
In some circumstances, a person who doesn't have a DUI conviction can still be charged with a second offense. Some states consider similar offenses or some types of dismissed cases to be prior DUIs.
All states have zero-tolerance laws. These laws make it illegal for drivers who are younger than 21 to have even a small amount of alcohol in their system. Don't assume these "lesser" offenses won't affect a driver who is 21 or older and charged with DUI. Some states count these underage DUI convictions as prior DUIs—meaning a new DUI arrest could be charged as a second offense.
DUI first-offender and diversion programs are available in some states. These programs allow a court to dismiss a DUI charge after a defendant has completed specific requirements, such as probation or alcohol treatment. Even if a DUI case is dismissed after completing a diversion program, it usually will count as a prior DUI conviction.
Most states also have some form of expungement, allowing certain criminal convictions to be removed from someone's record for most purposes. However, if you've had a DUI conviction expunged, it generally will count as a prior conviction if you face a subsequent DUI.
The consequences of a second DUI conviction are usually more serious than those for a first DUI. For example, the penalties for a second-offense DUI often include:
Also, there are lots of costs for a first-offense DUI, like attorney fees and insurance rate increases, which can significantly raise the amount you'll actually end up paying.
In most states, a first or second DUI is a misdemeanor—unless they include an aggravating factor like death or injury. But a few states make a second DUI a felony (most states make a third or fourth DUI a felony). Though serious, misdemeanors generally don't have the long-term negative effects as felonies.
Felonies can carry long jail or prison sentences. But they also can have severe collateral consequences, such as losing the right to vote or not being able to work in some professions.
Because laws vary by state and second-offense DUIs can carry serious penalties, it's normally a good idea to have a lawyer for a DUI case.
You also can read our state-specific articles to learn about the laws for second-offense DUIs in your state.