News just breaking that the United States Supreme Court will hear both the DOMA (Defense Of Marriage Act) and Proposition 8 cases.
The next step will be for the Court to issue a scheduling order in both cases which will set the timeline for when arguments will be heard. However this does mean that a ruling on both issues will be issued during this court term, or by June/July of 2013.
The best guess at this point is they would hear arguments during the March sitting which runs from March 18-27.
Obviously this story will be developing over the coming days as the court issues more detailed instructions to the parties but in the Proposition 8 case it appears they want to hear arguments over whether or not the supporters have standing under Article III.
This issue deals with the fact that in the appeal of the ruling striking down Proposition 8 nobody from the State of California (IE governor or attorney general) chose to defend the law. There is considerable question as to whether or not private citizens can step in and defend the case. Indeed in a case involving an Arizona law that the government chose not to defend the Supreme Court explicitly ruled that private citizens do not have standing to intervene and defend a law.
In the event that the court determined that the supporters did not have standing then the case would become moot and the original ruling holding Proposition 8 to be invalid would stand.
Regarding DOMA, the court is hearing the appeal on the issues relating to whether the federal government can deny benefits to same sex couples who are legally married under state laws. It is not considering whether or not the section of DOMA that allows one state to refuse to recognize a same sex union from another state. So even if DOMA is struck down in this case it would not mean Alabama has to recognize marriages from Vermont.