Five key facts about Tuesday’s hearing on same-sex marriage before the U.S. Supreme Court.

1. The case in point is Obergefell vs. Hodges. James Obergefell is one of a group of petitioners who seek to overturn Ohio's ban on same-sex marriage; Richard Hodges is director of the Ohio Department of Health. The court has joined the Ohio case with those from Tennessee, Kentucky and Michigan. The justices hear arguments on Tuesday but are not expected to rule until late June, at or near the conclusion of their current term.

2. At issue are two central questions: whether the Constitution requires the states to permit same-sex marriage and whether states must recognize the marriage of couples who are wed in another state.

3. Georgia's constitutional ban on gay marriage is not before the court, but the justices' decision will apply nationwide. If they rule that the bans in Ohio, Tennessee, Michigan and Kentucky are unconstitutional, Georgia's ban will fall with those of the 12 other states that have them. Including Georgia and the four whose cases are before the court, the states are: Arkansas, Louisiana, Mississippi, Missouri, Nebraska, North Dakota, South Dakota and Texas.

4. The justices take their seats at 10 a.m. They have set aside 2½ hours to hear oral arguments, quite a bit longer than the usual 90 minutes. A transcript of the proceedings, plus the audio record, will be posted at supremecourt.gov later in the day Tuesday.

5. What will happen? Many court watchers believe that a majority of the court will vote to overturn the bans on gay marriage and make it legal nationwide. Justice Anthony M. Kennedy, the swing vote on the nine-person court, most often votes with the conservative wing. But he has sided with the liberal wing in two key cases involving gay rights, and he wrote for the majority in overturning the federal Defense of Marriage Act in 2013:

DOMA instructs all federal officials, and indeed all persons with whom gay couples interact, including their own children, that their marriage is less worthy than the marriages of others. The federal statute is invalid.