DUI on private property not in car

What is the name of your state? Illinois

At 11:30 pm my b/f and i were heading to my house, we passed the cop who was sitting in a vacant lot. at 12:05 a.m. i was arrested on DUI charges.

The officer was called to my house because my boyfriend and i were in the front yard argueing. The witness stated that he heard noise, got out of bed, went to the other room, looked out the window and saw the two of us fighting so he called the officer and told him to get over there. when the officer arrived, i was arrested for a DUI.

The officer stated that he had seen me 30 minutes earlier and thought nothing of it because i was not driving erradictly or out of the ordinary.

How is it possible then that i was arrested for a DUI?

Are your sure you are reading the charge correct and it isn't for "Drunk in Public"???

If it is in fact DUI, then you have a pretty strong case for dismissal (you could have been stone sober when driving, then gotten home and drained a bottle of Jack Daniels!).