The U.S. Supreme Court on Monday temporarily halted gay marriages in Utah, but the constitutional question of whether a state can ban those unions is racing to the high court faster than many of the justices might have expected just six months ago.

Last June, the justices in Hollingsworth v. Perry, a challenge to California’s Proposition 8, a constitutional amendment banning same-sex marriages, did not reach the major question: whether a state, consistent with equal protection guarantees, may define marriage as the union between a man and woman. Instead, a 5-4 majority held that the proponents of Prop. 8 lacked standing to defend it.