Supreme Court mulls same-sex marriage rights nationwide

The US Supreme Court has heard arguments that will ultimately decide whether the US Constitution allows for the right to same-sex marriages. The court’s final opinion will be announced by the end of June.

Oral arguments in the case -- known as Obergefell v. Hodges -- will concern challenges to state bans on same-sex marriage in four states: Kentucky, Michigan, Ohio, and Tennessee.

The first 90 minutes of the court’s session on the case centered on whether the Constitution’s guarantees of due process and equal protection under the law demand that states must offer equality to gay couples. The next 60 minutes regarded whether states must recognize same-sex marriages from other states.

Same-sex marriage is already legal in 37 of the 50 US states, including the District of Columbia. Only 11 years ago, Massachusetts became the first state to offer equal marriage rights, exemplifying how fast a once contentious social issue – which played a major role in the 2004 presidential election, for example – has turned along with public opinion.

Last week, a Washington Post-ABC News poll found a record-high 6 in 10 Americans support same-sex marriage. Nearly the reverse was true a decade ago, the Post reported, saying that polling at the time found support for equal marriage rights was opposed, 58 percent to 39 percent.

A study recently released by the Williams Institute found that, since 2004, support for same-sex marriage has gone up by an average of 2.6 percent in every state and Washington, DC. The study also reported that by 2016, support for gay marriage will reach at least 40 percent in every state.

"There have been some assertions that attitudes in states like Alabama have not changed when it comes to marriage equality," said Andrew Flores, the report’s co-author. "Actually, as time goes on, those states will be the states where we should expect to see even more change."

In 2013, the court rejected in a 5 to 4 decision a federal law that defined marriage as only between a man and woman for the purposes of receiving federal benefits. Justice Anthony Kennedy, the swing vote in that decision and who will likely be the deciding vote for the current case, wrote in the court’s official opinion that the statute’s top purpose was “to disparage and to injure those whom the state, by its marriage laws, sought to protect in personhood and dignity.”

The 2013 decision did not offer blanket marriage rights nationwide, but it did begin a cascade of states reversing their positions on same-sex marriage, as legal challenges had validation from the nation’s highest court.

The 16 plaintiffs in the case have the backing of the Obama administration. They say that state bans on same-sex marriage violate the Constitution. The court’s final decision will hinge on its interpretation the 14th Amendment's equal protection clause.

The four states attempting to protect their bans are backed by many religious and conservative groups who argue that the traditional definition of marriage must be maintained, and that states are allowed to discriminate against same-sex couples.