The rules regarding drunk driving are often complicated enough that they can catch people off-guard. While you probably realize that you can be arrested if you're caught driving a car with a blood alcohol content (BAC) over the legal limit, there are several other situations that can also lead to your arrest — and they might surprise you.

Here are some of the unexpected ways in which people find themselves charged with driving under the influence (DUI) of drugs or alcohol:

When They Blow A 0.0% On A Breathalyzer

You don't have to blow anything on a breathalyzer test to be arrested for a DUI. Even if no alcohol is detected in your blood, you can face a DUI charge on the word of the arresting officer alone. Often, the officer will claim that you were driving "erratically" and use just about any traffic violation as a pretext for a stop. Since there's no roadside test kit that can tell whether or not you're under the influence of something other than alcohol — like marijuana or even over-the-counter allergy medication for a cold — you can still be charged.

When They're Home After A Night Out

Some people will take the chance and get behind the wheel after having a drink or two. When they arrive home safely, they're relieved — until there's a knock on the door hours or days later from the police. They may have been reported by a bartender, caught on camera causing property damage with their car, or caught on a traffic camera driving erratically. Often, they'll make their situation worse by admitting that they'd been drinking before they realize where the conversation is going!

When They're Merely Sitting In The Car

Maybe you realized after you got to your car that you weren't as sober as you thought when you first stood up. In your attempt to be responsible, you put the keys in your pocket and you lay down in the back seat for a nap. Well, under most state laws, that means that you are still in control of the vehicle and "operating" it. It doesn't matter if the ignition is off. It doesn't matter if you weren't in the driver's seat. In theory, as long as you have the capacity to control the vehicle, you're guilty of a DUI.

There are a lot of complicated issues that are involved in any drunk driving case — and situations like these can be particularly problematic. If you've been charged, talk to a DUI attorney promptly. For more information, contact local professionals or visit sites like http://www.chichesterlaw.com.