(CN) - The Campaign for California Families can't intervene in a lawsuit challenging the constitutionality of California's Proposition 8 because the group has the same goal as the parties already listed in the case, the 9th Circuit ruled.
The group said the Official Proponents of Prop. 8 and ProtectMarriage.com do not adequately represent its interests. But the circuit found that but the group failed to show that the parties conceded any "necessary" elements in the case.
The groups have "identical interests" in seeking to uphold Prop. 8, the state ballot initiative that defined marriage as solely between a man and a woman.
"Any differences are rooted in style and degree, not the ultimate bottom line," Judge Margaret McKeown said in ruling Campaign out of the debate and affirming the district court's denial of its motion to intervene.
Campaign says it goes further than the Prop. 8 defenders, and aims to hold up the opposite-sex definition of marriage in every marriage-related statute in California.
But Campaign only pointed to one other marriage-related measure, Proposition 22, which has nearly identical language to Prop. 8, McKeown said.
"When pressed at oral argument to put some meat on the bare bones of the claim that its interest is broader than that of the Proponents, the Campaign was unable to do so," the ruling states.
Prop. 8 was voted into law last November, prompting Kristen Perry and several gay and lesbian residents to file suit under 14th Amendment claims in May 2009.
Previously, the district court granted the City of San Francisco's motion to intervene in part, but denied intervention to a coalition of gay and lesbian advocacy groups.
The appeals court affirmed denial of the group's motion to intervene, saying Campaign's entrance would delay proceedings and outweigh any benefit of participation.
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