WASHINGTON — Utah's amendment banning same-sex couples from marrying is unconstitutional, a federal judge ruled Friday afternoon.

"The court hereby declares that Amendment 3 is unconstitutional because it denies the Plaintiffs their rights to due process and equal protection under the Fourteenth Amendment of the United States Constitution."

The ruling came a day after the Supreme Court of New Mexico interpreted its own state constitution as requiring that same-sex couples there be able to marry.

Although officials will be appealing the ruling, the Friday decision would make Utah the 18th state in the U.S. that allows same-sex couples to marry if it stands. An appeal would be heard by the 10th Circuit Court of Appeals.

"The federal district court's ruling that same-sex marriage is a fundamental right has never been established in any previous case in the 10th Circuit. The state is requesting an emergency stay pending the filing of an appeal," an official statement from the office of Acting Utah Attorney General Brian Tarbet noted. "The Attorney General's Office will continue reviewing the ruling in detail until an appeal is filed to support the constitutional amendment passed by the citizens of Utah."

A notice of appeal was filed by Utah officials with the trial court, prompting the court to transmit the trial court record to the 10th Circuit Court of Appeals.

Earlier, Utah Gov. Gary Herbert said in a statement, "I am very disappointed an activist federal judge is attempting to override the will of the people of Utah. I am working with my legal counsel and the acting Attorney General to determine the best course to defend traditional marriage within the borders of Utah."

With no stay issued immediately to keep the ruling from going into effect, however, the court's judgment in the case went into effect immediately when issued by the clerk at 4:28 p.m. local time. [Update at 3:40 a.m. Saturday, Dec. 21: State lawyers have now filed a request that the 10th Circuit immediately put same-sex couples' marriages on hold.]

And, couples in Salt Lake City did get married on Friday.

According to KSL-TV, "District Attorney Sim Gill said that he has advised clerks to proceed with the marriages, saying 'As of right now, if somebody gets in line and applies, there is no prohibition against it as a matter of law.'"