I'm happy to rest my case on most of this... I think the open-minded will conclude you're out to lunch, even some who are pro-legalization. Especially on the poor muzzled girls who dare not speak.

A few things...

Not at all. The man has one simple way of staying safe: never have sex with an underage girl.
BINGO!!!!! That is the very crux of your intentions, Ethan!

I have no idea why you think that is somehow surprising. I favor an age of consent, and "never have sex with an underage girl" is an obvious implication. What's more surprising is that I'm willing to be compassionate towards any exceptions at all.

Girls are just a special case of the general problem...
In other words, by "special case" you again argue that one group should be granted a sentimentally based advantage over another

No, your reading comprehension failed. See that word "just"? It specifies the meaning (especially common in mathematics) where something that appears to be different isn't fundamentally different and does not need special treatment. As in... in the conditions for declaring a stalemate in chess, "perpetual check" is a special case of "repeated positions".

If it was actual justice you were concerned about, then you would be willing to do the work to uncover evidence on a case-by-case basis regardless of how difficult and non-expedient it may be

That doesn't work in reality. Working hard to uncover evidence doesn't mean you can find it. Everyone agrees the man had intercourse with the 12-year-old. He says she agreed to it. She says she struggled and said "no". Even if the prior probability of his case is .02 (1 in 50), he can still likely get off under the "reasonable doubt" standard. No amount of diligence is going to uncover decisive evidence.

I do not think humanity is "perfectible".

It's a different topic, but I've never seen how anyone can seriously aspire to a stateless society without believing in the perfectibility of humanity. I don't know what else keeps the free riders, thieves, and others looking out for their own selfish interest from sabotaging the system.