A Harvard University American history professor testified in federal court in San Francisco Tuesday that she believes same-sex weddings would not hurt the institution of marriage and could even strengthen it.
Nancy Cott, the author of a book on the history of marriage in the United States, testified on the second day of a trial in which a lesbian couple and a gay couple are challenging California's ban on same-sex marriage.
The two-week trial is the nation's first on a federal constitutional challenge to restrictions on same-sex marriage.
The two couples claim California's measure, enacted by voters in 2008 as Proposition 8, violates their rights under the U.S. Constitution to due process and equal treatment.
U.S. District Judge Vaughn Walker will decide the case without a jury. The outcome is expected to be appealed to the U.S. Supreme Court.
Cott was asked by Theodore Boutrous, a lawyer for the plaintiffs, whether she believed extending marriage to same-sex couples would be beneficial.
"I would accept that, yes, amplifying its entry could be very beneficial," Cott said.
She also said expanding marriage to lesbians and gays would promote what she described as the American value of responsible raising of children.
Walker joined the questioning to ask Cott the historical reason why marriage in the United States is regulated by state governments rather than by private institutions.
Cott said the structure is derived from early colonists' reliance on the English tradition of civil law.
Cott was the first expert witness to be called to the stand by plaintiffs, following testimony Monday by the two couples, Kristin Perry and Sandra Stier of Berkeley and Paul Katami and Jeff Zarrillo of Burbank.
The second expert witness, Yale University history professor George Chauncey, began testifying Tuesday afternoon about the history of discrimination against gays and lesbians in the U.S.
The sponsors of Proposition 8 will present their side of the case in the second half of the trial. Their experts are slated to testify on topics such as the traditional definition of marriage, whether children fare better in opposite-sex marriages and whether sexual orientation is a matter of choice.