It’s slippery slope week.
Here’s a snippet from Justice Antonin Scalia’s dissent on yesterday’s SCOTUS ruling on gay marriage:
When the Court declared a constitutional right to homosexual sodomy, we were assured that the case had nothing, nothing at all to do with “whether the government must give formal recognition to any relationship that homosexual persons seek to enter.” Id., at 578. Now we are told that DOMA is invalid because it “demeans the couple, whose moral and sexual choices the Constitution protects,” ante, at 23—with an accompanying citation of Lawrence. It takes real cheek for today’s majority to assure us, as it is going out the door, that a constitutional requirement to give formal recognition to same-sex marriage is not at issue here—when what has preceded that assurance is a lecture on how superior the majority’s moral judgment in favor of same-sex marriage is to the Congress’s hateful moral judgment against it. I promise you this: The only thing that will “confine” the Court’s holding is its sense of what it can get away with.Â
Justice Scalia may indeed be correct about the alleged inconsistency; The court may have previously held that Lawrence v Texas wouldn’t entail gay marriage, but then in Windsor they use the legality of “homosexual sodomy” to justify not discriminating against gay marriages.  This, he maintains, shows the slippery slope from “homosexual sodomy” to gay marriage.
A few points.  First, since I’m not a legal scholar, I don’t know if the court has to maintain its promises–or whether the court can make promises like this. The gay marriage case wasn’t before the court at the time, and, as far as I know, the court decides only the cases it has before it. It would seem completely wrong for them to adjudicate such things in advance.
Second, inconsistencies are not ipso facto signs of dishonesty. I like to think my current correct views are inconsistent with my past incorrect ones. I also sincerely hope that my future correct views are inconsistent with my current incorrect ones.
Third, not all slippery slopes are fallacious. The court has recognized a right to “homosexual sodomy.” This means that homosexual relationships are not inherently inferior to heterosexual ones. This does in fact seem to entail that homosexual commitments differ in the same regard: i.e., not at all.