>since we ultimately have free will, it doesn't matter what is or isn't a crime, since God will judge all of us by His eternal laws
States have the authority and responsibility to recognize and enforce such laws as are in conformity with the natural law and contribute to the common good of the people.
As sodomy is a crime against the natural law, states have a right to recognize this crime as a crime and punish it with a just punishment.
The only remaining question, in determining whether sodomy should be illegal, is determining whether punishing it contributes to the common good. This determination must of its nature be concrete, limited to a given time and place, and therefore is impossible to make in totally absolute terms.
However, strong arguments can be made that in virtually if not actually every existing case, it would be better for the common good if sodomy was criminalized and punished.
One line of argument, based on the fear of God, would literally point to what happened to Sodom as proof that sodomy should be illegal for any state that wants to survive the divine wrath.
Another would point to the infinitely blooming, ever freshly demonic spiral of negative practical consequences that we observe sodomy to create for society. Just to name a few: gay-specific STDs, the creation of an "underclass" of homosexuals agitating for new "rights" every year, the degradation of same-sex platonic friendships when suspicion of homosexuality becomes too common, the slanders against prominent historical figures being "claimed" by the gays, the fact that normalizing sodomy has made it more common, the notoriously high promiscuity of sodomites, and… oh, yes, the giant elephant in the room of correlation between homosexuality and child abuse.
A third argument would say that legalizing or decriminalizing sodomy sends a message via "implicature" that "we no longer consider this a bad thing" and thereby causes scandal ipso facto.