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Last week, it was reported that David Epstein, a political science professor at Columbia University, was being charged with third-degree incest. Epstein is alleged to have carried on a three-year consensual sexual relationship with his daughter, who is now 24. The relationship is said to have ended in 2009. While the story has met with predictable outrage and revulsion, a number of bloggers are also taking the opportunity to launch an inquiry into the nature of incest itself, and whether the laws against it make any sense. In particular, writers are exploring the differences between homosexuality and incest, which conservatives sometimes equate as examples of immoral, destructive sexual practices.

Why Do We Criminalize Incest? wonders Eugene Volokh at The Volokh Conspiracy. "Is it that bans on gay sex are irrational but bans on adult incest are rational, and rationality is all that's required for regulations of adult sex? ... Is it that [Lawrence v. Texas] rested on the fact that bans on gay sex largely foreclose all personally meaningful sexual relationships for those who are purely homosexual in orientation, whereas incest bans only foreclose a few possible sexual partners?"

People Have a Natural Aversion to It, argues Razib Khan at Discover. "I'm not too interested in the argument against first-degree incest," writes Khan, "because I think this is a practice which is aberrant" because of "biological dispositions most humans have which make it unthinkable ... Human nature has dispositions in many cases which are not 'hard-wired.' But the disposition in this case is so strong that I believe arguing about the legality of consensual adult incest is an academic matter. The discussion is only surfacing because of its possible relevance to another issue, gay marriage."

This Pretty Much Demands a Law Based in Religion "The question of incest is a perfect illustration of the limits of legally based morality and the inability to establish any limits when morality is divorced from the religious tradition from which it emerged," thinks the anonymous blogger at ShrinkWrapped. "There is almost no way to construct a rational, legally based morality that forbids incest between adults. Most of us have a visceral reaction of disgust when we think about incest because the taboos are so deeply ingrained but the incest taboo can not be supported by rational argument alone."

No, We Need Stronger Reasons for Outlawing Things "No matter what offense you're talking about, mere immorality... doesn't strike me as a good reason to make something criminal," writes Doug Mataconis at Outside the Beltway. "When it comes to actions between consenting adults, the fact that there's what might be called an 'ick factor' is not, by itself, sufficient justification to make the act illegal."

Here's the Rational Argument: Incest Explodes Families, explains William Saletan at Slate. "When a young man falls in love with another man, no family is destroyed," Saletan writes. But "incest spectacularly flunks this test. By definition, it occurs within an already existing family. So it offers no benefit in terms of family formation. On the contrary, it injects a notoriously incendiary dynamic--sexual tension--into the mix. Think of all the opposite-sex friendships you and your friends have cumulatively destroyed by 'crossing the line.' Now imagine doing that to your family. That's what incest does."

And That's Bad for Society, adds Jay Tea at Wizbang. Even when incest takes place between consenting adults, Tea writes, "the introduction of the sexual dynamic entirely within the family structure causes violence to society as a whole."

Does 'Consensual' Parent-Child Incest Exist? Salon's Tracy Clark-Flory talks to a law professor, J. Dean Carro, who lays out the case that it doesn't. "Regardless of the age of the child," says Carro, "there's still a theory that a parent is always a parent, a child is always a child and, as a result, there truly can't be a consensual sexual act."

Why Wasn't the Daughter Charged? asks Glenn Reynolds at Instapundit. "Why are they only charging the man in what's said to have been a consensual relationship between adults? Isn't that an equal protection violation? Where's the civil rights community on this?"

Because It's About Control, says Alexa Tsoulis-Reay at Slate. "Prosecutors could have made a case against the daughter, but when it comes to incest, the authorities tend to focus on one party... and blame tends to fall on whichever half of the incestuous couple has more control." Tsoulis-Reay goes on to cite J. Dean Carro's remarks in Salon, where it's noted that "children are generally assumed to be part of a 'protected class' even when they're above the age of consent."

Epstein Was a Big, Fat Liberal A number of conservative bloggers have gleefully pointed out that Epstein has blogged at The Huffington Post, where he praised Barack Obama and called Sarah Palin "weak" and "self-centered." "Epstein accused Republicans of 'taking hypocrisy in their personal lives to new levels of self-indulgent weirdness,'" writes Robert Stacy McCain. "Obviously, Epstein's an expert on 'self-indulgent weirdness.'"

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