You have always prided yourself on being a good driver. You’ve always been careful with consuming alcohol before getting behind the wheel; you know your limits and you err on the side of caution. You’ve had a safe driving record for the past 50 years—only an occasional speeding ticket. You’ve never had a DUI, never been arrested.
One night, you go to a restaurant with friends and you have the same glass of your favorite wine that you’ve enjoyed for years—the same glass of wine you’ve always been able to enjoy without it affecting your driving ability. But on your way home, you see a policeman’s lights in your rearview mirror. You pull over; the officer tells you that you were weaving, asks for your license and registration, then asks you to get out of the car. Before you realize what’s happening, you’ve been arrested on suspicion of DUI.
How did this happen? You’re always so careful.