For most DUI and DWI convictions—even a first misdemeanor drunk driving offense—jail time is a possibility. But the likelihood of receiving a jail sentence for driving under the influence generally depends on the circumstances of your case. Here are some of the main factors that influence the probability of serving time in jail for a DUI offense.
Of all the factors that impact on DUI sentencing, the number of prior convictions is probably the most important. All states structure DUI penalties around how many prior DUI convictions the driver has. What counts as a second or subsequent DUI depends on state law. In some states, prior DUI convictions count only for a certain number of years. In other states, prior DUIs stay on your record and count as priors forever.
As you could imagine, the penalties you can expect for a first DUI are less severe than those for a second offense, the penalties you can expect for a second DUI are less severe than those for a third offense, and so on.
Putting all other factors aside, you generally won't serve much, if any, jail time for a first DUI conviction. For first DUI offenders, there are often programs (like DUI court) that can minimize the consequences of a conviction. With a second DUI conviction, jail time becomes more likely but can still be avoided in many cases.
However, when a driver is convicted of a third DUI, there's a high probability that a conviction will result in the driver spending some time behind bars. For example, in California and Tennessee, a third DUI conviction carries mandatory jail time of at least 120 days. And in Montana and Kentucky, anyone convicted of a third DUI is looking at a minimum of 30 days in jail.
Blood alcohol concentration (BAC) is another factor that can have an impact on whether a driver spends time in jail for a DUI conviction. For instance, for a second DUI in Illinois, there's mandatory jail time only if the driver's BAC was at least .16%. And Pennsylvania law imposes mandatory jail time for first DUIs only if the driver's BAC was .10% or more.
But even in states that don't explicitly provide more severe penalties for high blood alcohol concentrations, BAC is a factor that judges are likely to consider in deciding how to sentence a DUI offender. Also, drivers with high BAC might be less likely to receive a favorable plea offer from the prosecution.
Judges and prosecutors aren't likely to be lenient to DUI offenders who caused an accident while driving under the influence—especially if someone was injured or killed. In fact, the laws of many states require substantial jail time for DUI offenses that resulted in serious injuries or deaths.
Illinois DUI offenders who cause great bodily harm, permanent disability, or disfigurement to another person can be convicted of a class 4 felony and face up to 12 years in prison. Similarly, in Vermont, DUIs involving injuries carries up to 15 years in prison.
Generally, causing the death of another person while operating a vehicle under the influence can result in DUI-enhancement penalties or vehicular homicide or manslaughter charges. In either scenario, the convicted driver is looking at quite a bit of time behind bars.