Haha, I was just there this morning! I was going to work after so I just wore business casual clothes (more on the conservative side though)... dress pants, button down, sweater, long coat. Anyways, most people there were either dressed down (i.e. - jeans) or in business cas. I only saw one person in a suit and that was someone's lawyer. I got off relatively easy... my fine was lowered (it was originally 170), the citation was reduced to 6 over, and I got half as many points as I was originally cited. I didn't have to say a word other than agreeing to a lesser offense after the cop offered it.
I would think that business casual would be fine - almost anything but jeans, sweats, shorts, etc. would work.