In Maine, a DUI (driving under the influence, we call it operating under the influence or OUI) is a criminal offense. There are a few states (like New Jersey) where a DUI is a civil offense for which you're not going to be in prison for. But here in Maine it's a criminal offense which means you can go to jail, you can lose your license, and you have a criminal record which lasts forever.
We have no expungement process for OUIs or any other crime; we have no way of sealing those records from the public. So if you are, in fact, convicted of the OUI criminal offense here in Maine, you're going to have a criminal record forever. Operating under the influence (and it's called DUI, or DWI or even OWI in some other states -- but here is OUI) means that you are operating a motor vehicle while under the influence of intoxicants. And that includes legal prescription medications for which you are taking in accordance with the directions as well as alcohol or any chemical substance -- we have a very broadly defined view on chemicals here in the state of Maine. In impairment, if you are operating under the influence they define impairment as “impairment to any degree, no matter how slight, as it affects your physical and mental faculties.”
We have a very tough OUI law here, and that means that you can be arrested and charged with operating under the influence if you're riding your lawnmower on your personal property, if you're operating your motorcycle down your private driveway and you're under the influence, if you're in a parking lot driving in your car -- it does not have to be on a public roadway. It doesn't even have to be in what we think of in a traditional sense of a motor vehicle.