Corbett's administration has filed a lawsuit seeking to block same-sex marriage licenses in suburban Philadelphia, where Montgomery County Register of Wills D. Bruce Hanes has issued more than 150 to gay and lesbian couples since July 24.
State attorneys said in a court filing Wednesday the gay marriage licenses have no "value or legitimacy" and can't be defended in court. They compared gay and lesbian couples to children, who can't marry because a 1996 law says marriage is between a man and a woman.
Corbett released a statement Thursday calling it a poor analogy.
"The case involving Montgomery County revolves around a very basic question: Does a public official have the authority to disregard state law based on his own personal legal opinion about the constitutionality of a statute?" he said. "The analogy chosen in the legal brief filed on August 28th is inappropriate."
Corbett had come under fire from Democrats and advocacy groups. Equality Pennsylvania issued a statement earlier Thursday taking his lawyers to task over the legal argument.
"If there is one thing we can all agree on, it's that all people deserve to be treated with respect," said the group's executive director, Ted Martin. "The statements made by the attorneys do not simply defend the laws of the state; they deny loving, committed same-sex couples the dignity they deserve."