The Supreme Court will hear opening statements Tuesday in Obergefell v. Hodges, a historic case that will decide whether same-sex marriage is a constitution right.

The lead plaintiff, Jim Obergefell, is a Cincinnati real estate agent challenging Ohio’s same-sex marriage ban. It was upheld last year by the Sixth Circuit, creating a split that sent the case to the Supreme Court. Obergefell’s husband, John Arthur, died of ALS in 2013, just 3 months after they were married.

Richard Hodges is the director of the Ohio Department of Health, the office that refused to accept Arthur’s death certificate listing Obergefell as “surviving spouse,” because it did not recognize their Maryland marriage.

The consolidated case also includes plaintiffs from the other Sixth Circuit states—Kentucky, Michigan, and Tennessee—and the court’s decision is expected to cover all of them.

There are two questions at issue in the case, and they’ll be addressed separately in today’s two-and-a-half-hour oral arguments. One: Are states required by the Fourteenth Amendment to issue marriage licenses to same-sex couples? Two: Must states recognize marriages performed in other states where they are legal?

The court is expected to split 5-4, with the liberal contingent of Justices Ginsburg, Breyer, Sotomayor and Kagan, plus Justice Kennedy in favor, the New York Times reports. Kennedy, author of the decision that struck down the Defense of Marriage Act, will likely write the opinion.

Chief Justice Roberts may also vote in favor of same-sex marriage, the Times speculates, but he’ll only join that side if he’s presented with a narrow way to do so.

A decision is expected in June.

[Photo: AP Images]