Pennsylvania is the only Northeastern state that does not allow same-sex marriage or civil unions.
"Marriage is more than a word. It is a commitment between two people who love each other," explained Evan Smoak. "It's a right that should be afforded to all consenting adults, regardless of sexual orientation."
Smoak, and his husband, Zachary, will celebrate one year of marriage this weekend, except their matrimony isn't recognized in Philadelphia, where they live.
A state law passed in 1996 bans any recognition of homosexual unions.
"We are the land of the free and the home of the brave, and I want to start acting like that," said Pennsylvania Attorney General Kathleen Kane.
Kane was met with cheers and smiles Thursday at the National Constitution Center in Philadelphia. Two weeks after the United States Supreme Court struck down the federal ban on gay marriage, the fight is coming to the Keystone State.
"Denying equality is the very definition of discrimination," said Kane.
Ten couples, along with the ACLU, filed a lawsuit Tuesday against the state, seeking to legalize gay marriage. Kane said she won't defend the challenge in court.
"I cannot ethically defend the constitutionality of Pennsylvania's version of DOMA, where I believe it to be wholly unconstitutional," she explained.
Legally, it's the attorney general's duty to defend the constitutionality of state laws, but the law also says the attorney general can allow lawyers for the governor's office to defend a lawsuit if it's more efficient, or in the state's best interests.
"In deciding whether I have to perform the parallel duties of representing the agencies of this commonwealth, it was in conflict of my other duty of protecting and defending the constitution of the United States and Pennsylvania," said Kane.
She said she's leaving the job to Gov. Tom Corbett.
"Today, the attorney general chooses to protect those without high-priced lawyers, all those who suffer discrimination and inequality," Kane added. "Those thousands of families who have been denied of the dignity and respect that the constitution protects and guarantees in marriage equality."
"It's really good to know that the highest-ranking lawyer of the state of Pennsylvania is behind us," said Zachary Smoak.
But not everyone feels the same way.
"Marriage is defined very clearly as between a man and a woman," said Marilyn Hartman, with El Shaddai Ministries.
"I know that in this state there are people who don't believe in what we're doing, and I'm not asking them to believe in it," said Kane. "I'm asking them to believe in the constitution. I'm asking them for tolerance. I'm asking them for understanding, and I'm asking them for equality and due process."
Corbett's office will not comment on the lawsuit.