WASHINGTON (CBS/AP) — The lawyer who argued before the Supreme Court in favor of upholding California’s ban on gay marriage learned during his handling of the case that one of his children is gay. Now Charles Cooper says his own view of same-sex marriage is evolving.

The revelation is an unexpected footnote in the years-long debate over the California measure struck down by the Supreme Court last year.

Cooper learned that his stepdaughter Ashley was gay as the Proposition 8 case wound its way through appellate court, according to journalist Jo Becker’s forthcoming book, “Forcing the Spring: Inside the Fight for Marriage Equality.” And with the Supreme Court ruling now behind him, Cooper cast his personal opinion on gay marriage as evolving.

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