Proposition 8 trial hears testimony that gay marriage would undermine marriage

The head of a think tank on marriage and family testified at the Proposition 8 federal trial Tuesday that same-sex marriage would weaken marriage and possibly lead to fewer heterosexual marriages, more divorces and “more public consideration of polygamy.”

But under cross-examination, David Blankenhorn, founder and president of the Institute for American Values, acknowledged that he wrote in a book in 2007 that the U.S. would be “more American on the day we permit same-sex marriage than we were on the day before.”

Blankenhorn was called as an expert witness by lawyers defending Proposition 8 against a constitutional challenge by two same-sex couples. He is an author and researcher who is not associated with any university. He earned a master’s degree in history in England, where he studied the history of labor unions.

Blankenhorn testified that he later worked as a community activist in low-income neighborhoods in Massachusetts and Virginia, where he became interested in the effect of fatherless families on children.

After testifying that marriage was designed for two heterosexual parents to bear and raise children, Blankenhorn said he decided during the last two years to support domestic partnerships for gays and lesbians as a “humane compromise.”

He said he previously had feared domestic partnerships would undermine marriage and discriminate against gays, but concluded that they were more legalistic arrangements than marriage.

Under cross-examination by David Boies, an attorney for challengers of the ballot measure, Blankenhorn admitted he knew of no study that showed children reared by gay couples fared worse than those raised by heterosexual parents.

Blankenhorn also conceded that same-sex marriage would probably “improve the well-being of gay and lesbian households and their children.”

A spokeswoman for proponents of Proposition 8 said she did not know the context in which Blankenhorn made the statement in his book that same-sex marriage would make the United States “more American.”

Earlier in the day, a political scientist hired by defenders of Proposition 8 admitted under cross-examination that prejudice played a role in the passage of the 2008 initiative that banned same-sex marriage.

“At least some people voted for Proposition 8 on the basis of anti-gay stereotypes,” Claremont McKenna College professor Kenneth Miller testified during the third week of the trial.

Boies, who cross-examined Miller, read aloud written statements Miller made that said minorities were vulnerable to ballot initiatives, and that federal courts needed to step in and protect them. One of the statements was from a paper Miller wrote in 2005.

Miller was hired by the Proposition 8 campaign to testify that gays and lesbians today have significant political power. The issue of power is important in the legal analysis over whether gays and lesbians need stronger federal constitutional protection.

Boies pressed Miller to say Roman Catholicism is the religion that has the most adherents in California, with about 30% of the state’s population identifying itself as Catholic, followed by Southern Baptists.

Trying to show that gays lack power to protect themselves at the ballot, Boies said the Catholic Church teaches that homosexual acts are a “serious depravity” while the Southern Baptist Convention says homosexual acts are an “abomination.”

maura.dolan@latimes.com