[JURIST] Supporters of Proposition 8 [text, JURIST news archive], California’s same-sex marriage [JURIST backgrounder] ban, asked the US Supreme Court [official website] on Tuesday to uphold the law after two federal courts found it unconstitutional. In their nearly 500-page petition [text, PDF], backers of the ban stressed the necessity for the court to decide “whether the ancient and vital institution of marriage should be fundamentally redefined to include same-sex couples.” In their plea, the petitioners, including Alliance Defending Freedom [advocacy group], relied upon the Equal Protection Clause of the Fourteenth Amendment [text] to argue that the US Constitution does not prohibit California “from defining marriage as a union of a man and a woman.” The Supreme Court is likely to hear a case on gay marriage [SCOTUSblog report] under Proposition 8, or the Defense of Marriage Act (DOMA) [text, JURIST news archive], in its upcoming term.

In June, the US Court of Appeals for the Ninth Circuit [official website] denied [JURIST report] a similar petition filed by Proposition 8 supporters to rehear their case before the entire court. Proponents of the ban filed their plea in February after a three-judge panel voted 2-1 [JURIST reports] earlier in the month to overturn the law, finding that it violated the Due Process and Equal Protection Clauses [Cornell LII backgrounders] of the Fourteenth Amendment. Proposition 8 was approved by California voters [JURIST report] in November of 2008.