According to the NYT story on the closing arguments, the judge hearing the case seemed skeptical of the bland claims made by opponents of gay marriage:

Vaughn R. Walker, the chief judge of the Federal District Court in San Francisco, repeatedly questioned lawyers defending the measure — Proposition 8, passed by California voters in 2008 — over their position that marriage is, simply put, for making babies.

“The marital relationship is fundamental to the existence and survival of the race,” said the defense’s leading lawyer, Charles J. Cooper. “Without the marital relationship, your honor, society would come to an end.”

But Judge Walker, who will decide the case, dogged Mr. Cooper for hard evidence of that claim, noting that there are no rules prohibiting marriage between people who cannot have children.

Over the course of several hours, Judge Walker also sharply questioned the qualifications of one of Mr. Cooper’s witnesses and his assertion that marriage “serves a societal purpose that is equally ubiquitous.”