First of all, I believe the best thing we can do to prevent predatorial sex upon the vulnerable is to teach and empower them to be aware of the dangers of these advances and to be able to resist. This is the real key.
Tinkering about with legislation is very much secondary, and is a bit of a smoke screen, hiding away what really needs to be done.
Teenagers will ignore the law for the most part whatever it is. Most "right-thinking" adults will be not engage in predatorial sex in any case outside the zone of social stigma. Those who break social stigma in this regard are quite likely to ignore legislation in any case.
For "right-thinking" adults, social stigma and mores will be the main factor in judging what is right and wrong. I am not certain that an "age of consent" law influences these to any large degree, but I guess it has some effect.
Now none of this to say that there shouldn't be some attempt made to use the law as a stick to discourage the predatorial practices via an age of consent law, and to influence social mores. But we should, I think, bear the following in mind:
a) Let us be aware that whatever the age of consent legislation this will have minimal impact on the problem.
b) The occasional prosecution that might result against predators might give us some sort of intuitive sense of vengance (glad to see the B**tard locked up) but in the great scheme of things, it's not really going to make young people much safer, as such prosecutions will likely only ever be a tiny fraction of the consensual but yet predatorial underage sex that occurs.
c) The damage caused by predatorial sex by a 16 year old on another 16 year old can be just as great as a 20-something or 30-something on another 16-year old depending on the circumstances.
I know people who are 15 with the emotional maturity and responsibility levels of many 30 year olds and vice versa. This is the strange world we live in.
For example, which is morally worse?
- A 19 year old who has consensual sex with 15 year after dating for 6 months and using contraception.
- A 15 year old having consensual sex with another 15 year old after getting that person drunk and using no contraception at all.