The ruling also invigorated attorneys for six gay couples to file a federal lawsuit in Denver asking for an injunction stopping all officials from enforcing Colorado's same-sex marriage ban. Voters approved the constitutional ban in 2006.
Even if an injunction succeeds, the U.S. Supreme Court is expected to be the final authority on the matter.
"We are standing together today on the side of love," said Kate Burns, who along with partner Sheila Schroeder is among the couples who filed suit.
Meanwhile, Attorney General John Suthers warned Hall she will face unspecified legal action from his office if she doesn't stop issuing marriage licenses to gay couples.
Suthers said his office and Boulder County should appeal to the Colorado Supreme Court to determine whether Hall has the authority to issue the licenses. Suthers said in his letter to Hall that while the 10th Circuit ruling is an "important landmark," Colorado law will remain unchanged until there's a final ruling.
Hall had asked Suthers if she could have until July 10 to reply to him. Suthers agreed but remained adamant that she stop issuing licenses immediately.
Hall responded that she would continue giving licenses to gay couples.
"Our request was essentially denied as the terms for more time were contingent on stopping the issuance of same-sex licenses," Hall said in a statement, adding she believes the licenses she's issuing are legal.
Suthers' spokeswoman Carolyn Tyler said the attorney general "will focus on pursuing another legal strategy to secure compliance with Colorado law," but she did not elaborate.
Mari Newman, one of the attorneys filing suit, said the legal action was filed in part to support Hall, whom Newman believes is acting lawfully.
"We are seeking, among other things, to vindicate the right of the Boulder clerk and recorder," Newman said.
After the 10th Circuit ruling, two of the couples in the lawsuit sought marriage licenses in Denver and Jefferson counties and were denied.
The lawsuit alleges the state's same-sex marriage ban violates due-process and equal-protection rights guaranteed by the U.S. Constitution.
"Colorado law unlawfully denies the issuance of marriage licenses, and refuses to recognize the marriages of certain couples, based solely on the sex of the persons in the marriage union," the lawsuit says.
Although some of the couples in the lawsuit have civil unions in Colorado, the lawsuit calls them unequal and an inadequate substitute to marriage.