[JURIST] Lawyers for groups seeking to overturn California's new domestic partnership law [text; Lamda Legal factsheet] argued their case in a state court Friday. The law went into effect January 1 and gives gay couples who register as domestic partners nearly every spousal right granted under state law including automatic parental status and responsibility for each others debts. Opponents claim the statute violates Proposition 22 [text], a California state initiative that defines marriage as between a man and a woman. Attorneys for the Proposition 22 Legal Defense and Education Fund [official website] told the 3rd District Court of Appeals [official website] that Proposition 22 implicitly bars lawmakers from granting marriage-like benefits to domestic partners. The court did not indicate when it would rule on the matter. AP has more.