Marriage — modernly — is seen as sort of unalloyed good, says law professor Melissa Murray. “Everyone would like to get married, or most people would like to get married. Certainly, most people’s mothers want them to get married.”

Murray teaches family law at UC Berkeley. She says the marriage equality movement has built up the idea that marriage is this wonderful thing that everyone should want. And there are a lot of benefits to being married in the United States. People who are married have better financial outcomes than people who aren’t. They are often healthier (especially men), and they have access to a range of public and private benefits, like Social Security and shared employee health and other benefit plans.

But she says there’s a darker side to marriage that’s been overlooked.

“What the marriage equality movement really did not think about is that there is a kind of normalizing process that goes on in marriage,” says Murray. “Marriage signals that these people — the sexual relations that they have — are respectable, are valued, are worthy.”

And she says, you can’t make that kind of claim about one set of people and their intimate lives without illuminating what is disreputable about other people’s sexual relationships. “Getting more people into marriage actually highlighted that other people were outside of it and therefore, undisciplined, unregulated and problematic.”

To really understand Murray’s view on marriage, it’s important to take a look at the rather complicated history of marriage.

In the mid-1800s, women had very few rights, and marriage was necessary for the economic provision of most women who were not working outside the home. And, although it may surprise modern listeners, sex outside of marriage was a crime. As Murray explains, the criminal regulation of sex made clear that marriage was the licensed site for sexual activity.

“Marriage was where you had sex,” says Murray. “That’s an important aspect of it. Marriage interacting with criminal law for regulating sex. For identifying certain kinds of sexual acts as productive and valuable and other kinds as unproductive, destructive, and indeed criminal.”

Marriage worked as a kind of state-imposed sexual discipline. Those having sex within marriage were literally “in law,” while unmarried people having sex were sexual “outlaws.”

The close interaction between criminal regulation of sex and marriage meant that marriage could even be used as a form of punishment for certain sex crimes. If a man seduced an unmarried woman of “chaste disposition” with the promise of marrying her, and then didn’t follow through, the man could be charged and sent to prison for up to 20 years in some states.

“Interestingly, there was a defense for it,” Murray says. “The defense was simply that the man could get out of it by marrying the woman. So, there are these amazing scenes where all of a sudden this site of a trial was transformed into a wedding. No one thought the defendant was getting away with something by being married. If he was married, he literally had a ball and chain. He had someone he had to support. He would likely have a family to support. He would have to be sober, enterprising, productive and if he was abiding by his marriage vows, sexually faithful.”

Although a man can’t be prosecuted for a crime of seduction anymore — such laws fell out of favor in the early 20th century — marriage recently was prescribed as a sort of cure for bad behavior.

Just a few months ago, in August 2015, after a man got into a barroom brawl, a Texas judge ordered the man to marry his girlfriend or spend a few nights in jail. Scared that he’d lose his job if he took the jail time, the defendant reluctantly agreed to get married.

Although marriage has changed over the years, and people have more freedom to define the boundaries of their own marriages, Murray says there is a lot that hasn’t changed.

“I think if you ask anyone who is married, there is still a very stark gender differentiation in the amount of household labor that women do. And there certainly remains a persistent gap in caregiving that falls along gendered lines in most marriages. So, we’ve changed a lot, but in some ways, we haven’t changed at all.”

Marriage isn’t for everyone, Murray says, and there should be a variety of alternative options for those who wish to be in a committed, recognized relationship, but don’t want to be married for any number of reasons.

Ironically, the marriage equality movement may signal the death knell of efforts to promote a wider range of relationship recognition options. Already, the State Department has announced that it’s phasing out domestic partnership benefits. Now that marriage is available, same-sex couples — like straight couples before them — are expected to get married in order to receive benefits.

“I think one of the questions going forward is will we think more seriously about what to do about those kinds of relationship forms. Or will marriage really be a one size fits all kind of model for everyone.”

Melissa Murray has written extensively about marriage. You can find her 2012 article “Marriage as Punishment” in the Columbia Law Review, and her latest piece “Obergefell v. Hodges and the New Marriage Inequality” will be published in the August 2016 issue of the California Law Review.