A Colorado judge has struck down the state's ban on gay marriage.

“The Court holds that the Marriage Bans violate plaintiffs' due process and equal protection guarantees under the Fourteenth Amendment of the U.S. Constitution,” Adams County District Court Judge C. Scott Crabtree said in his 49-page ruling.

Colorado is the only state to recognize gay and lesbian couples with civil unions. (Wisconsin and Nevada offer domestic partnerships, which offer limited benefits.)

“The existence of civil unions is further evidence of discrimination against same-sex couples and does not ameliorate the discriminatory effect of the Marriage Bans,” added Crabtree, who was appointed to the bench in 2001 by Republican Governor Bill Owens.

Crabtree put his ruling on hold to “avoid the instability and uncertainly which would result.”

Evan Wolfson, president of Freedom to Marry, applauded the ruling in a statement.

“Yet another court has concluded that there is no good reason for denying gay couples the freedom to marry, and has found marriage discrimination unconstitutional,” Wolfson said. “It is time that Colorado's gay couples and their loved ones be able to share in the joy and security that marriage brings, and time for the Supreme Court to bring the freedom to marry home nationwide. Every day of denial is a day of wrongful deprivation.”

The lawsuit is separate from a federal challenge filed last week by six same-sex couples after the Tenth Circuit Court of Appeals in Denver upheld a lower court's ruling striking down Utah's ban.

(Related: Utah to appeal gay marriage ruling to Supreme Court)

The ruling reverberated in Colorado, which is under the Tenth Circuit's jurisdiction. Buoyed by the decision, Boulder County Clerk Hillary Hall began issuing marriage licenses to gay couples. On Wednesday, a judge considered a request from Attorney General John Suthers to force Hall to stop issuing such licenses. A ruling is expected this week.