LITTLE ROCK, Ark. – A judge on Friday struck down Arkansas’ ban on same-sex marriage, saying the state has “no rational reason” for preventing gay couples from marrying.

Pulaski County Circuit Judge Chris Piazza ruled that the 2004 voter-approved amendment to the state constitution violates the rights of same-sex couples.

“This is an unconstitutional attempt to narrow the definition of equality,” Piazza wrote. “The exclusion of a minority for no rational reason is a dangerous precedent.”

The ruling came nearly a week after state Attorney General Dustin McDaniel announced he personally supports gay marriage rights but that he will continue to defend the constitutional ban in court. McDaniel’s office said he would appeal the ruling.

An attorney for the group of same-sex couples challenging the prohibition said he hadn’t talked with his clients and didn’t know if they would seek marriage licenses when county offices open Monday morning.

“If I was them, I would be there waiting for the door to open,” attorney Jack Wagoner said.

The amendment banning gay marriage was passed with the overwhelming support of Arkansas voters. Piazza’s ruling also overturns a 1997 state law banning gay marriage.

In his ruling, Piazza cited the U.S. Supreme Court’s 1967 decision that invalidated laws on interracial marriage.

The U.S. Supreme Court last year ruled that a law forbidding the federal government from recognizing same-sex marriages was unconstitutional. Since then, lower-court judges have repeatedly cited the decision when striking down some of the same-sex marriage bans that were enacted after Massachusetts started recognizing gay marriages in 2004.

Federal judges have ruled against marriage bans in Michigan, Oklahoma, Utah, Virginia and Texas, and ordered Kentucky, Ohio and Tennessee to recognize same-sex marriages from other states.

In all, according to gay-rights groups, more than 70 lawsuits seeking marriage equality are pending in about 30 states. Democratic attorneys general in several states — including Virginia, Pennsylvania, Nevada, Oregon and Kentucky — have declined to defend same-sex marriage bans.

The head of the Human Rights Campaign, the largest U.S. lesbian, gay, bisexual and transgender civil rights, praised the ruling.

“This victory is an essential step on the journey toward full equality for all,” said HRC President Chad Griffin, an Arkansas native. “

But the leader of the group that campaigned for the ban said the judge was undermining the will of voters.

“This ruling undermines marriage because once people start redefining marriage, there seems to be no place to stop,” Arkansas Family Council President Jerry Cox said.