- In some contexts, such as sexual content, it is desirable to be
rigourous in confirming factors such as the subject's age, and 'release' or permission - it is this area which is lacking a bit at the moment.
Perhaps you explain this in your essays (it's late and I have to be up early, so please excuse me not reading them!), but how do you intend to do that? The only reliable information we really have is the photo itself - we can guess the age by looking at the subject and if the subject is clearly posing we can be reasonably sure they intended the photo to be taken, but that's all. I don't see how we can possibly be rigorous about it.
I'd like to illustrate by drawing your attention to two images currently being discussed on the 'Commons' project;
http://commons.wikimedia.org/wiki/File:Topless_Barcelona.jpg and
Topless sunbathing is a legitimate topic for discussion and it usefully illustrate by such a photo. So that rates pretty highly on "utility". I think it rates pretty low of "potential for harm" since the subjects aren't identified and they chose to sunbathe topless on a public beach. A photo where we have the subjects' permissions would be better, but I don't see how we could be sure of that (any kind of posing would ruin the photo - it would turn it from topless sunbathing to glamour modelling, a completely different topic). So I think this photo is appropriate.
http://commons.wikimedia.org/wiki/File:That%27s_why_my_mom_always_told_me_to...
I struggle to see any value in that photo. There are plenty of other photos to illustrate miniskirts in general and I don't think highlighting this particular risk in wearing such clothing really requires illustration. So that rates low on "utility". It also rates low on "potential for harm" since it is almost impossible to identify the subject (it rates slightly higher due to being accidental, albeit reckless, rather than intentional as the sunbathing was, but that is overruled by the fact that you can't identify the subject). I think this photo falls into the "Virtually harmless, but what's the point of causing any harm at all?" category.