Former President Bill Clinton is calling on the Supreme Court to overturn a law he signed that bars federal recognition of same-sex marriages.

Clinton says the Defense of Marriage Act is incompatible with the Constitution. He says he signed the law in 1996 to avoid legislation that would have been even worse for gays.

Clinton writes in a Washington Post op-ed that American society has changed. He says he now realizes the law discriminates against gays and provides an excuse for others to discriminate, too.

The Obama administration has stopped defending the law in court, and the Supreme Court is expected to take up a challenge to it later this month.

Separately, the high court is also considering whether California's gay marriage ban should stand.