A coalition of groups that advocate for the civil rights of lesbian, gay, bisexual and transgender people today filed a brief urging the U.S. District Court not to vacate last year's historic ruling invalidating Proposition 8. Lambda Legal, the National Center for Lesbian Rights, the ACLU of Northern California and Equality California filed the friend-of-the-court brief in Perry v. Brown in response to a motion filed last month by supporters of Proposition 8 that asked the court to undo last year's decision in that case. The Prop 8 supporters contend that now-retired Chief Judge Vaughn Walker should have declined to hear the case because he was in a long-term relationship with another man, and that the judge's 135-page decision, which followed a three-week trial, should be invalidated for that reason.