I think that's an important point. Anyone arrested on such flimsy grounds would no doubt easily beat the charge with a good lawyer. But as yourself this: supposing you were genuinely innocent, would you really want to go to court and make your arrest public knowledge? Or might you be tempted simply to plead guilty, get a slap on the wrist, and keep things quiet?
I would say what a GREAT job the officer was doing in aggressively pursing sexual preditors, and thank him for his public service. I would then say that I understand how my actions could have been interpreted as such, however the officer simply misinterpreted them, and that his desire to protect the public is very much appreciated.. I would then state that I would be happy to have the officer present his case to a jury who I am certain would agree that my actions in the bathroom were just simply misinterpreted by the officer... and then I would make a public offer to pay for the arresting officer to attend a "refresher class" on sexual preditors so that he could be more effective at his job....
HOWEVER, on the other hand IF I WAS GUILTY.. I would plead guilty and HOPE the public believes me when I say "I LIED to the judge when I plead guilty..." which is VERY unlikely..