MONTPELIER, Vt. (AP) — Vermont is commemorating its first-in-the-nation civil union law and subsequent marriage equality legislation with a historic-site marker on the State House lawn.

The marker was ceremoniously unveiled Tuesday by two of the three gay couples who were plaintiffs in the Vermont Supreme Court case that led to civil unions, along with Beth Robinson, a lawyer at the time who served as co-counsel in the case and is now a Supreme Court justice.

"Since its founding, Vermont has been a leader in protecting and furthering civil rights, embracing diversity and promoting tolerance," Republican Gov. Phil Scott said.

Passing the civil union legislation in 2000 was the right thing to do and it took courage and commitment by many, said Scott, who was in the state Senate from 2001 to 2011 and voted for full marriage equality in 2009.

On Tuesday, he commended legislators, advocates and then-Gov. Howard Dean, a Democrat, for passing the policy that made Vermont the first state to grant legal recognition to same-sex couples.

State lawmakers passed marriage equality legislation in 2009, and the U.S. Supreme Court legalized same-sex marriage nationwide in 2015.

Having a marker commemorating the events is "unbelievable," said Lois Farnham, of Middlebury, who attended the ceremony with her partner, Holly Patterbaugh. The couple, now in their 70s, wore matching tie-dyed T-shirts bearing the message "It's Just Love."

Former state Rep. Herb Russell, a Democrat who received a civil union and later got married in Vermont, sought the marker because he believed the historic event deserved to be commemorated.

"We're very proud of the fact that the first civil union law was in Vermont," he said. "And I felt strongly that we needed to document that history and take great pride and claim our role in the historic path of equality in this country."

Democratic Rep. William Lippert also reflected Tuesday on the events that led to marriage equality in Vermont. He, too, received a civil union and later got married under the law.

"Little did I know how profoundly the courage of (then-House Speaker) Michael Obuchowski and (then-Gov.) Howard Dean would affect my life personally and the lives of thousands of Vermonters and tens of thousands of lesbian and gay couples in Vermont, across the country and indeed throughout the world," he said.