One way or another, the nation's highest court will make history. But it is taking a huge risk by wading into such a sensitive issue as gay marriage.

The most immediate impact of the Supreme Court's long-anticipated announcement Friday that it will hear a challenge to Proposition 8 – the 2008 measure passed by voters to ban same-sex marriage in California – is that gay couples waiting to marry in our state will have to wait some more.

The long-term effect depends on how sweeping a ruling the justices eventually issue.

If they legalize same-sex marriage nationwide as a constitutional right, it could trigger a backlash – just as the 1973 Roe v. Wade decision, which sanctioned abortion before many Americans were ready, strengthened the anti-abortion movement.

If, on the other hand, the court upholds Prop. 8, it could blunt the growing momentum at the ballot box and in public opinion in favor of gay rights.

Either way, the court's decision won't be the final word for many Americans.

While polls show there's growing acceptance of gay marriage, particularly among the young, it remains a divisive issue. On Nov. 6, voters in Maine, Maryland and Washington made their states the first to approve gay marriage by popular vote, increasing to nine the states allowing same-sex unions. Minnesota voters refused to put a gay marriage ban in their constitution.

But 39 states still prohibit same-sex marriage, including 31 that have enshrined bans into their constitutions.

It is in this landscape that the justices are treading. They are expected to hear arguments in March and issue their ruling in June.

Justice Anthony Kennedy of Sacramento could again provide the pivotal vote. He wrote a 2003 ruling overturning a Texas anti-sodomy law in which he said the state could not "demean" gays by treating them as second-class citizens. As an appeals court judge in 1996, Kennedy struck down a constitutional amendment adopted by Colorado voters that banned laws protecting gays and lesbians. In February, a divided panel of the 9th U.S. Circuit Court of Appeals in San Francisco relied extensively on that Kennedy ruling in overturning Prop. 8.

The Supreme Court could go several ways with the case. It could throw out the appeals court ruling and put Prop. 8 back into effect. It could allow gay marriage in California, but not require it in other states. Or it could address the broadest question of whether the Constitution's guarantee of equal protection gives all Americans the right to marry, regardless of sexual orientation.

The court also agreed Friday to consider a limited challenge to the Defense of Marriage Act, the 1996 federal law that defined marriage as between a man and woman. The justices will look at a section of the law that prevents gay couples from receiving benefits otherwise available to married couples. The court passed on cases that challenged another part of the law that declares that no state can be forced to accept a gay marriage from another state.

This term, the justices will also decide other significant cases on affirmative action in higher education and the future of the Voting Rights Act. The court's conservative majority has the opportunity to redefine what equality means today in America.

Our democracy's march forward has been about becoming more tolerant and protecting Americans against discrimination.

To go backward would be a colossal mistake.

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