The degree to which you can find yourself in legal trouble for cycling while intoxicated varies depending on where you are. In some places, bicyclists cannot be charged under a particular state’s DUI law.
Brendan Kevenides has a blog called The Chicago Bicycle Advocate where he answers questions and offers legal advice specifically for cyclists. As cyclists, we find a lot of misinformation about our rights and responsibilities. There’s nothing like a cold beer after a long ride. What happens if you have one too many? Kevenides addresses this in the article Biking Under The Influence.
Know your rights. Keep partying, just be safe.