In the wake of the U.S. Supreme Court’s two recent rulings validating gay marriage, a Boston College Law School professor has come out and admitted what gay marriage adversaries have long argued: incest and polygamy are just around the bend.

“You know those opponents of marriage equality who said government approval of same-sex marriage might erode bans on polygamous and incestuous marriages?” asks the professor, Kent Greenfield. “They’re right.”

In a piece at the website of The American Prospect, the Catholic law school prof then goes on to challenge gay marriage supporters to differentiate totally acceptable gay and lesbian marriages from various forms of communal marriage and sibling love.

“The left is in this bind in part because our arguments for expanding the marriage right to same-sex couples have been so compelling,” Greenfield brags proudly. “Marriage, we’ve said, is about defining one’s own family and consecrating a union based on love. We’ve voiced these arguments in constitutional terms, using claims arising from the doctrines of ‘fundamental rights’ and equal protection.”

After a discussion of the famous sodomy case, Lawrence v. Texas, which waxes poetically about the “right to define one’s own concept of existence,” Greenfield then pops the question: under such a legal rubric, “why can’t people in polyamorous relationships claim that right as well?”

He observes that he frequently hears a couple answers “in private conversations with leaders in the marriage movement”—that’s presumably the gay marriage movement, not the traditional marriage movement. “The first is that there is no political energy behind a fight for incestuous or polygamous marriages. The second is that they would be fine if those restrictions fell as well but, in effect, ‘don’t quote me on that.'”

The University of Chicago grad proceeds to gut five distinctions that could stop the slippery slope from gay marriage to incest and polygamy. He then advises his comrade intellectuals to “fess up” and accept these relationships openly and honestly.

“We can admit our arguments in favor of marriage equality inexorably lead us to a broader battle in favor of allowing people to define their marriages, and their families, by their own lights,” he concludes.

(h/t The College Fix)

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