This is part of the reason why casual accusations of pedophilia have always disturbed me. Because it can lead even people who in most other circumstances would be considered pro-justice and pro-human rights into mini-Mengeles.
And I've seen people just throw out the accusation without even prompt or justification, just because they hate somebody (maybe for other good reasons) and want to see if it sticks. It's fucked up.
Then there's other cases like that one where that 18-year-old got jumped for being baited into going on a date with another 18-year-old, while under the impression that she was... at least 18. A couple of people posted about that already.