Like whist, whilst, and self-abuse, the word sodomy has an old-fashioned ring to it. You don't even see it alluded to much anymore, except in punning tabloid headlines about the situation in Iraq. But it—or its kissin' cousin, the nearly as archaic-sounding "deviate sexual intercourse"—can be found in the criminal codes of thirteen states of the Union, where it is punishable by penalties ranging from a parking-ticket-size fine to (theoretically) ten years in prison. Even at this late date, many people are vague about just exactly what sodomy is. Montesquieu defined it as "the crime against nature," which is not...