The following are editorials and commentaries about the U.S. Supreme Court's decision to weigh in on two cases involving same-sex marriage:

Bloomberg News Editorial:

The question before the Supreme Court is not whether to allow same-sex marriage, but how.

That should be the question, anyway. Last week the court agreed to hear two cases involving the constitutionality of same-sex marriage. Theodore Olson, one of the lawyers for proponents of same-sex marriage, called it "perhaps the most important remaining civil-rights issue of our time."

He is undoubtedly right about that. What the court must do is find a way to encourage the movement's progress without needlessly antagonizing opponents.

The court will probably hear oral arguments in March in the two historic cases. One concerns the legality of a provision of the Defense of Marriage Act, the 1996 federal law that defines marriage as "a legal union between one man and one woman." Under DOMA, gay couples in states where it is legal for them to marry can't claim federal tax breaks or other benefits that straight married couples receive.

The other case involves California's Proposition 8, which bans same-sex marriage. Opponents of the 2008 law say it is flatly unconstitutional, a violation of the 14th Amendment's guarantee of "equal protection of the laws." In February, a federal appeals court agreed.

By accepting these two cases, the court has delineated a choice familiar to civil-rights advocates for decades, and to defenders of American ideals of freedom for much longer than that: what kind of progress to accept.

In the DOMA case, the court could uphold, strike down or refine the federal government's right to define marriage. In effect, the issue would be adjudicated state-by-state. The California case is more straightforward: Either same-sex marriage is constitutional or it is not. In all 50 states.

As always, the legal options are slightly more complicated than that. But the dilemma is simple enough and is nicely captured by our friend Andrew Sullivan, who has done more than perhaps anyone to make the conservative case for same-sex marriage. "I am worried about two things," writes Sullivan, who is gay. "I'm worried that we will fail, and I'm worried that we will succeed."

After all, if we want to live in a country that allows gay Americans the same rights as all Americans - and we do - then how can we allow any limits on same-sex marriage? At the same time, acceptance of same-sex marriage is not something that can be imposed by judicial fiat.

Gay marriage is fast becoming a reality. The level of public support for same-sex marriage continues to rise, and just last month voters in three states legalized it, bringing the number to nine plus the District of Columbia as of Jan. 1. In politics and culture, support of same-sex marriage is becoming commonplace. Thankfully, there is little the Supreme Court can or should do about this.

What's more, the court's intervention on major social and political issues is not always helpful. One of the leading critiques of Roe v. Wade is that it was a legal short circuit of the political process; you can believe, as we do, in a woman's right to an abortion and also think that the court's 1973 decision inflamed an already divisive issue. Some proponents of same-sex marriage made this argument in recommending against the court's review of the California case.

In the law as in politics, there is an honorable tradition of dodging the question. It wouldn't necessarily be horrible if the court didn't pronounce next year that same-sex marriage is a constitutional right. It needn't even rule on the constitutionality of DOMA, although the law infringes on what is traditionally a state right. Whatever the court does, however, it should be careful not to impede the expansion of rights and the cause of fairness that help to define America.

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San Jose Mercury News:

Supporters of marriage equality will be on tenterhooks until June, when the Supreme Court is expected to decide on two cases: one challenging the constitutionality of Proposition 8, California's voter-approved ban on same-sex marriage, and the other challenging the Defense of Marriage Act, which denies federal marriage benefits to legally married gay couples.

We hope the Supreme Court will affirm the rulings of lower-court judges who have reversed both of these discriminatory laws. A decision upholding state-sponsored discrimination against gays and lesbians would be viewed widely as the Dred Scott ruling of our time

But whatever the decision, the court of public opinion soon will render it moot. The trajectory of changing attitudes on same sex marriage is inexorably headed toward full acceptance and legal status - something this newspaper has advocated for 20 years.

The trend is clear in California, where 52 percent of voters supported Proposition 8 just four years ago. In a May survey, 54 percent said they now support legal same-sex marriage, while just 40 percent were opposed. Even if the Supreme Court upholds the ban, voters here will overturn it themselves before long and join the nine states that now allow gays and lesbians to marry.

Nationally, 49 percent of respondents to an October Pew poll said they supported legalizing gay marriage, while 40 percent said they were opposed. That is essentially the reverse of poll numbers four years earlier. And the reason is obvious. Young people overwhelmingly support equality: An October Gallup poll found three-quarters of 18- to 29-year-olds in favor. Even in the conservative South, a more accepting younger generation eventually will overtake the old guard, even if it takes a bit longer.

Testimony in the Proposition 8 trial two years ago exposed the emptiness of the arguments against same-sex marriage. Supporters of the proposition presented just two witnesses, neither of whom could offer a shred of credible evidence that preventing gays from marrying promotes any legitimate state interest.

David Boies, the lead lawyer on the team seeking to strike down the gay marriage ban, explained the predicament faced by his opponents: "They didn't fail because they're bad lawyers; they failed because there isn't any evidence to support the argument they're advocating."

That's the reality in both cases the Supreme Court will hear in the coming months.

It will be far better for the country if the high court comes down on the side of equal rights in a way that settles the matter quickly and cleanly and allows divisions on social issues to begin to heal. But the battle for marriage equality has been won. Now it's just a matter of how the war will end.

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Michael Klarman, Harvard Law professor, writing for the Los Angeles Times:

On Nov. 6, for the first time in American history, a majority of voters in a state - indeed, in three states - approved same-sex marriage. On Friday, the Supreme Court decided to weigh in on the issue, granting review in cases challenging the constitutionality of the Defense of Marriage Act and in a case contesting the constitutionality of California's Proposition 8, which barred same-sex marriage.

DOMA is likely to prove the easier issue for the court, assuming the justices rule on the merits of either or both cases (there are procedural issues that, depending on how the justices are inclined, could block them from considering the merits). The relevant statutory provision bars congressional recognition of same-sex marriages lawfully performed in the states. This means, for example, that a same-sex couple lawfully married in Massachusetts is disqualified from receiving Social Security survivors' benefits that are available to married opposite-sex couples.

Several lower courts have invalidated DOMA on federalism grounds. Historically, Congress has usually deferred to state definitions of marriage. Supreme Court justices who care deeply about preserving traditional spheres of state autonomy ought to be troubled by DOMA, regardless of what they think of marriage equality. Conservative justices who prize federalism and liberal justices who endorse marriage equality may combine to invalidate DOMA by a sizable margin.

Indeed, for the court to uphold DOMA in 2013 would be surprising. Some sponsors of that law, enacted in 1996, defended it in blatantly homophobic terms, denouncing homosexuality as morally wrong and comparing it to polygamy and pedophilia. Supreme Court precedent forbids statutes to be rooted in animus or prejudice, and to a considerable degree DOMA was.

In addition, justices are not indifferent to public sentiment, and recent opinion polls show that Americans no longer support DOMA. One 2011 poll revealed that Americans favored its repeal by 51 percent to 34 percent. Even lower-court judges appointed by Republican presidents have been voting to strike down DOMA.

Predicting how the court will rule on the Proposition 8 case, which could clearly establish or deny a constitutional right to same-sex marriage, is harder. For starters, the justices are likely to divide 5 to 4, as they do on almost every important constitutional issue - including abortion, affirmative action, campaign finance reform, capital punishment, gun control and federal health-care reform.

As on most other issues, Justice Anthony M. Kennedy, probably the most powerful justice in the court's history, is likely to determine the outcome. His vote may turn on how he balances two seemingly opposing proclivities. On the one hand, Kennedy's rulings often turn dominant national norms into constitutional mandates to suppress outlier state practices. His decisions barring the death penalty for minors and the mentally disabled and invalidating state laws criminalizing same-sex sodomy fit this description.

On gay marriage, this propensity to use the Constitution only to suppress dissident practices would counsel restraint on the part of the court. Just nine states and the District of Columbia currently permit same-sex marriage. Intervening at this stage of a social reform movement would be somewhat analogous to Roe v. Wade, in which the court identified an abortion right that invalidated the laws of 46 states. Kennedy has rarely if ever used the Constitution so aggressively.

On the other hand, Kennedy authored the court's only two decisions supporting gay rights, explicitly embracing the notion of a living Constitution whose meaning evolves to reflect changing social mores. Moreover, Kennedy's opinions frequently treat international norms as relevant to American constitutional interpretation, and marriage equality is rapidly gaining momentum around the world.

Finally, language in some Kennedy opinions suggests an attentiveness to historical legacy, and the handwriting on the wall on marriage equality is crystal clear. Support among Americans has increased from less than 25 percent in 1990, to 30 percent to 35 percent in 2004, to more than 50 percent today. In addition, polls show that 70 percent of Americans aged 18 to 29 support gay marriage, and that is unlikely to diminish as these people age.

Many state legislators have explained their votes in favor of gay marriage on the ground that they wanted to be on the right side of history and to have their children be proud when reflecting on their parent's legislative record. Judges authoring opinions in support of gay marriage have frequently invoked examples of courts being on the right side of history. Chief Justice Margaret Marshall, the author of Massachusetts' pioneering gay-marriage ruling, has compared it to that court's 1790s ruling that barred slavery under the very same constitutional provision. Similarly, the California Supreme Court's decision in favor of gay marriage proudly invoked its landmark 1948 ruling that invalidated a state ban on interracial marriage.

In 1954, the court's ruling in Brown v. Board of Education, which invalidated racial segregation in public schools, split the nation in half. Within two decades, however, it had become iconic. A high court ruling in favor of marriage equality would similarly divide the nation in 2013. Yet, given how quickly public opinion is evolving, within a decade or so such a decision would probably also be almost universally applauded. What justice would not be tempted to author the opinion that within a few short years likely would become known as the Brown vs. Board of Education of the gay rights movement?