Julian Sanchez has a good post debunking the canard that "gays" are disproportionately responsible for child sexual abuse, that is unfortunately posited by the religious right. (And that such groups would spread such a blood-libel makes it hard for me to believe that they really do not hate homosexuals. I realize that having a sincere religious conviction against homosexual behavior does not a hater make. And many of these folks genuinely do not hate homosexuals. But the problem is, many of them do.)
Most surveys of instances of child molestation have found that male molesters of male children are typically not "homosexual" in any conventional sense (i.e. pursuing relationships with adult males). And that's important because the proportion of instances of child molestation that involve male-male contact is much higher than the proportion of gay men in the population. Those two facts are used by conservatives to claim that gay men are more likely than other men to molest children; the reason they're wrong about that is precisely because, in fact, the overwhelming majority of male molesters of male children are not "gay" in the colloquial sense.
The survey result is probably the result of men whose primary sexual attraction is to young boys (though they may be heterosexual or, more likely, totally asexual, in their relationships with adults) concluding that they must, therefore, be "gay" (since it is, after all, *boys* they're attracted to--the conservative argument). But psychologists and social scientists tend to regard pedophilia as, in a sense, a separate orientation of its own. If someone's primary sexual activity is screwing goats, you don't ask whether the goats are male or female to determine whether the person is "straight" or "gay".
This is true. For someone who is a true pedophile, it's the age of the victim which is the focus of their separate orientation. Sometimes pedophiles have a preference for little boys or little girls. Often they indiscriminately want children, regardless of gender. For instance, "reformed" pedophile Jake Goldenflame, was a married self-identified hetero man, apparently with no attraction to adult men, and *some* attraction to adult women, and was a typical true pedophile. He molested his own daughter and boys too.
Calling him gay or "bisexual" and lumping him in with the gay or bi community, because he molested little boys, is downright disingenuous.
So any study that purports to demonstrate that "gays" have a higher incidence of molestations by categorizing true pedophiles -- no attraction to adult men who molest little boys -- as "gay" is garbage. And that's what the religious right does when they claim, "gays are 3% of the population but make up 1/3 of all molestations...."
A few other important notes. Many of these studies also conflate pedophilia and ephebophilia, which likely have two completely different origins. Ephebophilia is sex with an underaged but post-pubescent teen. (And note, that in most cases I think it's wrong for precisely the same reason pedophilia is wrong: both activities harm the underaged actor involved.) There appears to be no separate "ephebophile" orientation, but rather this stems from a general heterosexual or homosexual orientation (although some with an ordinary heterosexual or homosexual orientation may have preference for underaged, but biologically adult, actors -- just as some have a preference for blonds v. brunette or short v. tall women, or a race preference, etc.).
And because ephebophilia is more "natural," it's also far more common than true pedophilia. True pedophiles, like Jake Goldenflame, are extremely rare from a statistical point of view. Whereas gays are somewhere between 2-5% of the population, pedophiles are probably a fraction of a one percent. But when we mix ephebophilia with pedophilia, then "pedophilia" seems much more common.
So a man lusting after a 15-year-old male or female, one who is clearly well into puberty (not all 15-year-olds are) most likely has a general homosexual or heterosexual orientation. And I'd be open to evidence that gays or straights are more likely to be involved in this behavior than the other.
However, given that up until very recently, heterosexual ephebophilia has been normalized throughout the history of Western Civilization (as long as it took place within the context of a marriage), given that for instance, without much of a fuss, Jerry Lee Lewis and Loretta Lynn (and countless non-celebrities) were both involved in ephebophile marriages where one party was an adult male, the other a 13-year-old girl, in the South in the 50s (the hey-dey of social conservatism), you aren't going to convince me that gays are more likely to be ephebophiles than straights.