GOP presidential hopeful Mike Huckabee on Sunday defended Kentucky county clerk Kim Davis for refusing to issue same-sex marriage licenses. When asked by ABC host George Stephanopoulos whether Davis had an obligation to uphold the law, even if she disagreed with it, Huckabee argued she did not.

“You obey if it’s right,” the former Arkansas governor said on “This Week.” “So, I go back to my question, is slavery the law of the land because Dred Scott said so? Was that a correct decision? Should the courts have been irrevocably followed on that? Should Lincoln have been put in jail? Because he ignored it. That’s the fundamental question.”

The 1857 Dred Scott decision is widely viewed as the worst Supreme Court ruling in history. In it, the Court ruled that no one with African ancestry could be a citizen of the United States and voided prior legislation that had blocked the expansion of slavery into parts of the country. Huckabee, like some other conservatives, argued that a 19th-century ruling requiring discrimination against black people is similar to a 21st-century ruling barring discrimination against LGBT people.

Davis has argued that her religious convictions bar her from allowing two people of the same sex to be legally recognized as married. Also on Sunday, conservative columnist George Will told Fox News that Davis had an obligation to resign from office if she would not abide by the law.