Well, since he chose to argue against DUI laws in general, rather than argue that walking ones bicycle in their own yard did not constitute DUI; I have a feeling that what really happened was:
The cops saw him riding down the sidewalk at night without a headlight. He makes it to his yard before the cops stop him. He plays word games by stating that he was stopped while walking his bike in his yard, but he leaves out the prior part of the story of his riding on the public sidewalk.
Therefore, the idiot deserves both the ticket for no headlight as well as the DUI bust.