This week, the Supreme Court will hear two cases that could lead to decisions changing the traditional definition of marriage. That definition, let's remember, is based on thousands of years of Western culture in which such a union has been between one man and one woman. The justices might change that definition to a union of any two adults.

Polls show that the acceptance of same-sex marriage in the United States has rapidly increased in just a single generation. Politicians in both parties have begun jumping on an expanding bandwagon, beginning last year with Joe Biden in the middle of a presidential campaign (which momentarily left his boss twisting in the breeze). Barack Obama later "evolved" from his previously stated opposition to same-sex marriage to support of it, though at the time, Obama declined to provide any direct action to change the definition of the institution.

Before the judiciary settles this question — or perhaps leaves it unsettled — it would behoove us to pause in this rush, and ask what purpose the institution of marriage serves in our society.

Let's start by refining the argument. Supporters of same-sex marriage talk of "legalizing" gay marriages, but that's not an accurate depiction of current law. No U.S. state, regardless of its definition of marriage, will prosecute same-sex couples who call themselves "married," nor should they, outside of an intent to defraud — which is a crime regardless of the sexual circumstances. In fact, the government has a very limited legitimate interest in sexual or living arrangements. Especially after the Lawrence v. Texas case, the government has no role in regulating sexual activity with the exceptions of consanguinity (close blood relations), use of force and victimization, commercial trafficking of sexual favors, and exploitation of minors.

No one wants the government to dictate who may or may not share a bed, outside of those exceptional circumstances. Those who choose to cohabit in non-traditional relationships have ample options for formalizing their arrangements through the private contract process, which government enforces but does not sanction. That leaves adults free to choose whatever sexual arrangements they desire outside of the actual prohibitions that are objectively applied to everyone. That is actual freedom and equality.

Marriage, however, is a unique status even apart from religious concerns, which I'll address later. Marriage licenses exist as government recognition of the unique procreative potential of heterosexual relationships. The government takes a special interest in that potential for good reason — because a failure of the procreators to act as proper guardians forces the government to build safety-net systems for children whose parents either cannot or will not provide for them. Marriage provides a structure for assigning responsibility for children potentially produced by heterosexual relations. Put simply, it fixes responsibility for paternity on the husband, regardless of who may have fathered the children during a marriage — a fact that more than a few cuckolded husbands have discovered during divorce settlements. That structure ensures that the state can enforce responsibility for the care of its most vulnerable citizens, even to the extent of criminal prosecution for neglect.

In Western societies, including the U.S., marriage has always been a forward-looking institution aimed at protecting and nurturing the next generation of children, not a love license for the adults of the present.

Most states, until relatively recently, provided incentives for marriage and disincentives for divorce. Social experimentation undermined both, and safety-net programs accelerated the process. Thanks to no-fault divorce laws that put the whims of adults over the needs of children, the results of devaluing marriage for heterosexual unions have produced heavy social costs for the past few generations that have fallen outside of the traditional family structure.

That being said, marriage recognition is a government policy just like all other statutory and regulatory policies. In a democratic republic, government policies are open for debate and change, either through direct democratic mechanisms like referenda or through legislative action by elected representatives of the voters. In a few cases, states have legalized same-sex marriage through those channels. While many disagree with those changes, few would argue that the process or the outcome was somehow illegitimate.

However, one case in particular presents a contradictory question to the Supreme Court. In pushing to overturn a referendum passed by a large majority in California that enshrined the traditional definition of marriage into the state constitution, the opponents of Proposition 8 argue in essence that both the process and the policy chosen by the voters are entirely illegitimate. Voters used a direct-democracy mechanism that has existed in California for decades to amend the constitution no differently than other such propositions, and affirmed the definition of marriage that has existed during the entire history of this country. The challengers don't like the outcome, and argue that nine justices should only accept as a legitimate result of that referendum a definition of marriage that until the last few years few would have accepted, and negate a legitimate outcome in an election. That's an argument for an oligarchy or an autocracy, not a democracy. 

Tolerance, it seems, works only in one direction — and that brings us to the religious argument, but not in the manner one might think.

While as a practicing Catholic my definition of marriage involves its sacramental character, I understand that others may not share my faith and perspective on its meaning or value. That, however, will not work both ways, as recent examples have made plain. For example, a baker in Oregon faces potential criminal charges for refusing to provide a wedding cake for a same-sex couple because of his religious beliefs. What happens when churches refuse to perform such ceremonies for the same reason?

Most people scoff at this question, but religions have partnered with the state on marriages in a way that bakers have not. Priests, ministers, rabbis, and imams act in place of the state when officiating at wedding ceremonies, and states that legalize same-sex marriage are eventually going to be forced by lawsuits to address that partnership, probably sooner rather than later. In similar partnerships, that has resulted in pushing churches out of business. 

Massachusetts demanded that Catholic adoption agencies, which handle private adoption in an arrangement that is less of a stand-in for government than officiating at weddings is, place children with same-sex couples. The Boston diocese opted to drop its adoption services rather than fight the state in court. Most recently, the federal government imposed a requirement on religious organizations and individual business owners to provide and/or facilitate free birth control and sterilization services even though doing so conflicts with their beliefs and doctrine. Part of the argument put forward in favor of this policy is that these religious organizations — especially Catholic health-care providers — partner with the government to deliver those services, and therefore have no right to stand on religious-liberty grounds. It's not difficult to see the writing on the wall when it comes to the ability of churches to perform a core sacrament in any meaningful sense once the government changes the definition of marriage.

The best outcome would be for Americans to recall the limited state interest in marriage and preserve it as a forward-looking institution, and return to incentivizing families rather than lowering barriers to failure. While society increasingly places no value on marriage except as a government love license, the best outcome would be to have government get out of the marriage business altogether, restricting itself instead to enforcing contracts. People that want to change the definition of marriage should use the proper methods in our form of government to address government policy rather than suing to overrule the will of the electorate. The worst outcome for both society and democratic processes would be for the Supreme Court to invalidate a fair election result to impose a new definition of marriage in California that voters made clear they didn't accept, and force the rest of the country to accept that outcome.