Sorry if I am venturing in late on this. A few of us here at MS, and as well, in this thread, appreciate your point of view, and also understand that in your country, the bar is set on purpose very low, with the intent of protecting as many people as possible from unwanted sexual experiences. We also have to keep in mind in this discussion that the interpretation of sexual assault in your country is different from others in other countries. What constitutes sexual assault where you live is what matters as those are the societal rules that govern your life, and those around you. I think you did the right thing.
I'd also like to put the issue of power on the table. The man with the offending behaviour obviously thought he had power, and could do whatever he wanted. His use of that power crossed the line in your country, and to not call the police would only have allowed him to retain his power, his control over others. To not call the police would have kept the secret, allowing the abuser to continue his abuse of others. I think you know where I am going with this. As adults now, we have the ability to say in a loud voice that no one should have to be exposed to another's sexual behaviour without their consent. We have the power. If we choose to not use it, that just lets the bad guys continue being bad. I'm sorry someone else got hurt by the bad guy. Maybe if someone else had called the cops a lot earlier, neither of the people who you wrote about might have been hurt.
In my country, women, not just in nudist colonies, but on the street, have the legal right to be able walk on the streets topless, if they so choose. When the case to obtain this right went to court, the decision was made that women's breasts are not, in and of themselves sexual any more than a man's. Its society's (predominatly men's) objectification of them that has resulted in the sexualization of the anatomy. Just thought I'd throw that in there for the hell of it.