When the Supreme Court considers the constitutionality of marriage for gay men and lesbians beginning this week, the justices will be taking a major step toward defining their own legacy.

In their first-ever review of same-sex marriage laws, the nine justices on the country’s highest court are hearing arguments on Tuesday and Wednesday on one of the most politically charged dilemmas of the day, bound with themes of religion, sexuality and social custom.

The paired cases will be heard at a time when opinion polls show surging approval for gay unions and when prominent individuals and groups, such as the American Academy of Pediatrics, have been announcing support for same-sex marriage on a nearly daily basis.

On Sunday, leading Republicans weighed in on the issue, taking positions across the political spectrum. Former Bush administration adviser Karl Rove said that he could envision a GOP presidential candidate supporing gay marriage in 2016, but leading social conservatives said such a move could seriously endanger the GOP’s hold on its grassroot supporters.

Many Republicans would still prefer the issue be left up to the states and are encouraging the high court justices to rule narrowly.

“They would be far better off to decide these two cases on the narrowest possible grounds,” former House Speaker Newt Gingrich said Sunday. A sweeping decision against gay marriage, he said, would be a “huge mistake” that would “undermine respect for the judiciary.”
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