The participation of the Church of Latter-Day Saints in a legal brief filed by religious groups in favor of California’s Proposition 8 is vexing an organization that advocates for LGBT Mormons. In a 38-page friend-of-the-court brief, filed before the Supreme Court Jan. 29, religious groups — including the Mormon Church — emphasize that justices shouldn’t strike down Prop 8 on the basis of religious support for the anti-gay amendment. The brief is signed by Von Keech, a Utah-based private attorney who has previously assisted the Mormon Church, as well as other private attorneys with his firm Alexander Dushku, R. Shawn Gunnarson and Kirton McConkie. “[O]ur members supported Proposition 8 based on sincere beliefs in the value of traditional marriage for children, families, society, and our republican form of government,” the brief states. “Only a demeaning view of religion and religious believers could dismiss our advocacy of Proposition 8 as ignorance, prejudice, or animus.” In a statement on Monday, Affirmation, a national group for gay and lesbian Mormons, questioned why the Mormon Church would participate in a legal brief in favor of Prop 8 after backing off its support of anti-gay measures since the passage of the California’s constitutional ban on same-sex marriage in 2008.