After nine days of trial, two same-sex couples who want to overturn Proposition 8 presented their final witness in federal court in San Francisco Friday, clearing the way for defense testimony to begin on Monday.
The couples claim that Proposition 8, California's ban on gay and lesbian marriage, violates their federal constitutional rights to due process and equal protection.
Proposition 8 was enacted by state voters in 2008. Its defenders at the trial before U.S. District Judge Vaughn Walker are the initiative's sponsors and campaign committee, ProtectMarriage.com.
The case will be decided by Walker without a jury and is expected to be appealed eventually to the U.S. Supreme Court.
The final plaintiff witness was psychology professor Gregory Herek of the University of California at Davis.
He testified that homosexuality is now considered normal by the psychiatry and psychology professions and that most gays and lesbians feel they have little or no choice in their sexual orientation.
Herek said he doesn't believe that people can change their sexual orientation through conversion therapy.
Proposition 8 attorney Charles Cooper told Walker that the defense will present only two expert witnesses, plus possibly a third witness to authenticate documents.
The two witnesses will be David Blankenhorn, president of the New York-based Institute for American Values, who will testify about marriage and family structure; and Kenneth Miller, an associate professor of government at Claremont McKenna College, who will discuss the political power of gays and lesbians.
The Proposition 8 proponents have withdrawn four other expert witnesses. But they have used cross-examination of plaintiff experts during the first two weeks of trial to try to support their claims that heterosexual marriage is rooted in tradition and is better for children.
Proposition 8 sponsors also contend that gay rights are not entitled to the highest level of legal protection because sexual orientation, unlike race, is allegedly a characteristic that can be changed.
The plaintiffs will rest their case in Walker's Federal Building courtroom Monday morning after putting final documents into evidence and playing several video clips of Proposition 8 campaign advertisements.
The defense testimony is expected to begin in mid-morning and to end on Tuesday.
Walker announced Friday morning that he will hear final arguments in the trial at a later date after he has reviewed the evidence.