As the Supreme Court prepares to hear arguments next week for and against the legalization of same-sex marriage, the public is increasingly coming down on the "for" side.
In fact, an ABC News-Washington Post poll released Monday (March 18) found that 58 percent of Americans now favor the legalization of same-sex marriage, a number that leaped from just 37 percent in 2003. The shift in opinion is dramatic compared with other social issues. Public opinion on abortion, for example, has barely budged since the 1970s.
Some of the change is likely the result of more advocacy and visibility by gay Americans. But marriage itself has changed, gradually toppling the gendered roles that once defined man and wife.
"Now we're organized in a gender-neutral way," said Stephanie Coontz, the director of the Research Council on Contemporary Families and author of the book "Marriage: A History" (Penguin Books, 2006).
"It's up to the individual couple to negotiate their roles and duties," Coontz said. "It's really easy for a heterosexual couple to say, 'That's what I've got, why shouldn't same-sex couples have it?'" [I Don't: 5 Myths About Marriage]
Out of the closet
Tolerance for gays and lesbians has gone up considerably. Some of this is generational: According to the Pew Research Center, 70 percent of the Millennial generation (born after 1980) supports legal same-sex marriage, compared with 49 percent of Gen Xers (1965-1980) and 38 percent of Baby Boomers (1946-1964). The Silent generation (1928-1945) is least likely to support same-sex marriage, at only 31 percent in favor.
But support within each of those generational brackets has risen over the past decade, too. For example, in 2003, only 17 percent of the Silent generation supported same-sex marriage.
Visibility of gays and lesbians has made part of the difference. When Pew asked people who had changed their minds from anti-same-sex marriage to in favor why they'd shifted their attitudes, the most common response (32 percent) was that they knew someone who was gay and that personal relationship had altered their opinion.
Republican Sen. Rob Portman of Ohio recently made headlines for altering his opinion in just this way. The senator came out in support of same-sex marriage in an op-ed in the Columbus Dispatch on March 15, saying that he'd changed his mind after his college-age son came out as gay.
Another 25 percent of Pew respondents simply said they'd grown more open or thought about it more, and 18 percent said legal same-sex marriage was "just inevitable." Another 18 percent cited love, happiness or the need for the government to stay out of relationship decisions.
As opinions have shifted, so has marriage. Getting married once meant signing on to traditional gender roles wholesale. Companies once refused to consider married women for employment, or required women who were getting married to resign. (IBM, for example, only altered this policy in 1951.) It wasn't until the late 1970s that women could sue for consortium, or the right to their husband's aid, support and companionship. Before then, a man could sue a third party that injured his wife (through medical malpractice, for example) on the grounds that her injury took away his right to consortium — she couldn't provide him with services and companionship he had rights to. But because women were legally inferior to men, a wife could not sue on behalf of her husband.
It wasn't until the Supreme Court case Griswold v. Connecticut in 1965 that married couples won the right to contraception. Assisted reproduction, such as it was back then, was also frowned upon. [7 Surprising Facts about The Pill]
"In the 1950s, at least two state courts held that assisted reproduction was adultery and the child was illegitimate," Coontz said.
Laws such as this gradually got overturned, Coontz said, making marriages far less gendered. At the same time, expectations that a married couple must procreate have declined — and assisted reproductive technology is far more acceptable for couples who can't have kids the old-fashioned way.
In other words, same-sex couples haven't changed marriage for straight people, as opponents of same-sex marriage often argue, Coontz said. Heterosexuals changed marriage first.
"It's the opposite sequence than what is described by opponents of same-sex marriage," she said.
Opponents of same-sex marriage tend to hold more traditional, gendered views of marriage than supporters, Coontz said. But given that heterosexuals aren't quizzed on their plans for splitting up the household chores or having babies before being handed a marriage license, it's hard to construct legal arguments around that view.
"It's harder for opponents to say every family has to have a guy who does this and a gal who does this," she said.
The Supreme Court will hear oral arguments in the case Hollingsworth v. Perry on Tuesday (March 26), reviewing a federal appeals court decision that found Proposition 8, which banned same-sex marriage in California, unconstitutional. On Wednesday (March 27), the Court will hear oral arguments in United States v. Windsor, a challenge against the Defense of Marriage Act (DOMA), which refuses federal benefits to same-sex couples in states where gay marriage is legal.
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Stephanie Pappas is a contributing writer for Live Science, covering topics ranging from geoscience to archaeology to the human brain and behavior. She was previously a senior writer for Live Science but is now a freelancer based in Denver, Colorado, and regularly contributes to Scientific American and The Monitor, the monthly magazine of the American Psychological Association. Stephanie received a bachelor's degree in psychology from the University of South Carolina and a graduate certificate in science communication from the University of California, Santa Cruz.