The U.S. Supreme Court's long-awaited decision on Proposition 8, California's ban on same-sex marriage, is due on Wednesday.
Chief Justice John Roberts announced at the close of a court session Tuesday that the panel will issue its remaining decisions Wednesday on cases argued during the current court term.
Those cases include challenges to Proposition 8 and the federal Defense of Marriage Act.
Proposition 8, enacted by state voters in a ballot initiative in 2008, provides that only marriage between a man and a woman is valid or
recognized in California.
It was challenged in 2009 in a civil rights lawsuit filed in federal court in San Francisco by two couples who want to marry.
The high court will rule on an appeal by the proposition's sponsors of a lower court decision that struck down the measure. The marriage ban has remained in effect during the appeal process.
The court has several options for ruling on the case, ranging from upholding Proposition 8 to dismissing the appeal.
The justices' questions and comments during a hearing in March suggest they may be inclined to favor either of two procedural options that would result in the invalidation of Proposition 8, thereby allowing same-sex weddings to resume in California as early as late July.
In those two potential scenarios, the high court itself would not rule directly on whether the measure violates the U.S. Constitution, but would in effect dismiss the appeal and reinstate a lower court ruling that struck down Proposition 8.
In one option, the court could rule that its hearing on the appeal was "improvidently granted," meaning that justices decided that they should not have taken up the case. That step would reinstate a 2012 decision in which the 9th U.S. Circuit Court of Appeals invalidated Proposition 8 on grounds that would apply only to California.
In another option, the court could say the sponsors of Proposition 8 had no standing, or legal authority, to appeal the case after Gov. Jerry Brown and state Attorney General Kamala Harris declined to do so.
That scenario would reinstate a broad ruling in which now-retired U.S. District Judge Vaughn Walker said in 2010 that Proposition 8 violates
the constitutional rights of due process and equal treatment.
The two sides dispute whether Walker's ruling would then apply statewide or only to the two couples who sued.
San Francisco City Attorney Dennis Herrera has said he is confident the lower court ruling would apply statewide.
He has estimated that same-sex weddings could resume in California by late July, following a 25-day period for sponsors to ask the high court to reconsider the case, plus a few additional days for a court mandate to be issued.