SANTA ANA, Calif. (AP) – A gay couple wants a federal judge to overturn state and federal laws against same-sex marriage, arguing that those laws violate their civil rights and are equivalent to racial segregation.

Calling gays “the most oppressed minority since slavery,” the couple’s attorney, Richard C. Gilbert, told U.S. District Judge Gary Taylor “It now falls to you to uphold the principles of liberty.”

The case is one of the few challenges to bans on same-sex marriage pending in federal court. Most litigation on the issue is in the state court system, where advocates believe they have a better chance of success.

The five-hour hearing focused on such basic questions as the purpose of marriage, the definition of discrimination and whether a federal court should get involved in an issue that is the subject of active litigation in state courts.

Taylor, after detailed questioning of all sides in the suit filed by Christopher Hammer and Arthur Smelt of Mission Viejo, said he would not issue an immediate ruling but would take some time to consider the arguments.

California recognizes only marriages between a man and a woman, and the federal Defense of Marriage Act allows states to disregard same-sex marriages performed in other states and foreign countries. Hammer and Smelt, both 45, had a private commitment ceremony in 1997 and applied for a marriage license from Orange County last year. They sued after they were turned down.

“It was something that needed to be done,” Hammer said of the lawsuit.

Lawyers for the county, state and federal governments and two private groups backing California’s same-sex marriage ban argued that the couple have failed to prove they have been victims of unconstitutional discrimination in their bid to gain official recognition of their marriage.

The attorneys opposing same-sex unions argued that the government has a legitimate and long-standing goal of encouraging marriage between men and women as a way to produce and raise children in stable environments.

“Marriage has always meant a man and a woman. That is what is fundamental about marriage,” said Scott Simpson, a Department of Justice lawyer.