Rep. Jerrold Nadler (D-N.Y.), ranking Democrat on the subcommittee, asked Gallagher if the children of Jen and Dawn BarbouRouske, a married same-sex couple from Iowa who were present during the hearing, should have parents who can receive the full protections of marriage or if she considers these children "expendable."

"I think no children are expendable," Gallagher replied. "Gay people have families that are not marital families, but they are families. I myself was an unwed mother, so I have firsthand experience with being in a family that's not a marital family. I don't think you need to have a message of stigmatization and exclusion to protect to an ideal."

Nadler, sponsor of DOMA repeal legislation in the House, interrupted Gallagher, saying "the whole point" of DOMA is stigmatization and exclusion, and pressed Gallagher further on why the institution of marriage benefits when same-sex couples are excluded.

"Because including same-sex unions as marriages denies at a public level that marriage is about an important way for getting together mothers and fathers and children," Gallagher said.