This rule certainly has the virtue of being easy to administer: To determine whether a marriage is legal in Kansas, a couple will need to show up at the clerk's office with a documented chromosome check and the clerk will issue a marriage license. But it's hard to square this rule with any of the arguments against same-sex marriage that we're used to. Assume, for example, that J'Noel decides she is a lesbian and finds a nice girl to settle down with in Wichita or Topeka. They decide to have a child, and like heterosexual couples who have biological problems procreating, use a little medical science to intervene. Or maybe they adopt. Their child (or children) will have legally married homosexual parents of the same (apparent) sex -- a configuration that many Kansans find intolerable -- because the court has tried to enforce state law against same-sex marriage.
J'Noel and her new wife could drop by the supermarket and shop arm in arm, with all the world, and the world's kids, watching. If they kissed, and anyone tried to make a big stink about it, J'Noel and her wife could simply brandish the Supreme Court decision, demonstrating the legality of their marriage. They would apparently be entitled to all the federal tax benefits married couples get, not to mention all the rights and responsibilities married couples have under Kansas law. In fact, they might fit the profile of a model "normal" marriage in Kansas, though one would have to see evidence of their chromosomal makeup to understand that.
In its decision, the Kansas court is up-front about the fact that the legislature is ultimately responsible for what the law says, and that the court is simply interpreting the law as best it can. But it's hard to see how the legislature could make a better job of it than the court did. It is difficult, if not impossible, to compulsively distinguish between same-sex and opposite-sex marriages without facing the profound question of what sex is and why it matters.
If the legislature does nothing, it permits homosexual transsexuals to marry people of what appears to be the same sex, leaving heterosexual post-op transsexuals out in the cold, along with all the non-transsexual homosexuals in the state. If the legislature sees a problem in legalizing apparent same-sex marriage, it could overrule the court and permit transsexuals to marry someone who is the opposite of their post-op gender, thus acknowledging that it is the appearance of opposite sex that is ultimately the guiding force in creating public policy. But, in order to apply that policy with any consistency, the legislature would then be obliged to prohibit heterosexual cross-dressers from (a) marrying, or (b) appearing in public with their spouses and expressing affection. Option (b) would certainly present some interesting First Amendment issues, and no one anywhere has proposed anything like option (a).
But that isn't the end of it. Most people, it's true, have either an XX or an XY chromosome set to determine their gender. But some people have more. What about those people who have three chromosomes? Who do they get to marry? How would that be decided? And what about children like the infamous John/Joan, who was born a male but whose parents approved an operation to have his penis removed after a botched circumcision and then raised him as a girl -- with very poor results. Unlike J'Noel, he/she never had a choice about the sex change. Who should someone like John/Joan be allowed to marry? And why should the state have any role in that decision?
The Gardiner ruling, in all its stunning complexity, should illustrate, better even than the cases dealing directly with same-sex marriage, how extraordinary it is for the state to be inserting itself into the relative gender of marital partners. Lesbians and gay men know, and Gardiner may help some heterosexuals to realize, that it isn't the relative sex of the partners that makes marriage valuable to both society and individuals, and it certainly isn't the appearance of opposite sex; it's the intimacy and satisfaction of the two partners. We all benefit from couples who support one another, emotionally, financially, spiritually and in all the other ways couples lean on one another.
The question at the heart of Gardiner is not whether J'Noel is a man or a woman, it's whether she is worth treating as a human being. As long as Kansans focus on the first question, it will be necessary for them to answer the second with a humiliating no.