A couple, dressed in Western attire, watch a ceremony at which Colorado Gov. John Hickenlooper signed the Civil Unions Act into law at the Colorado History Museum in Denver, Colo., on Thursday, March 21, 2013. Colorado Gov. John Hickenlooper gives a thumbs up as he celebrates with members of the legislature after he signs the Civil Unions Act into law at the Colorado History Museum in Denver, Colo., on Thursday, March 21, 2013. Rep. Mark Ferrandino, back left, and Sue Schafer, right, sponsored the bill in the House. Colorado Gov. John Hickenlooper is surrounded by member of the State Legislature as he signs the Civil Unions Act into law at the Colorado History Museum in Denver, Colo., on Thursday, March 21, 2013. A gay couple embrace during a ceremony at which Colorado Gov. John Hickenlooper signed the Civil Unions Act into law at the Colorado History Museum in Denver, Colo., on Thurssday, March 21, 2013. Anna Simon, left, and her partner Fran Simon hold their son Jeremy Simon, 5, who shows off his signing pen given to him by the governor at the ceremony where Colorado Gov. John Hickenlooper signed the Civil Unions Act into law at the Colorado History Museum in Denver, Colo., on Thursday, March 21, 2013. Hundreds looked on, with many chanting "Equal! Some wiped away tears and others hugged during the signing ceremony. "There is no excuse that people shouldn't have all the same rights," Hickenlooper told the crowd, which included dozens of gay couples and others watching from floors above. "It's not marriage, but it still gives us a lot of the rights," Martinez said. Because of that constitutional amendment, civil unions are the only option for gay couples in Colorado for now. "We today are remedying an exclusion that has gone on for too long," said Steadman, who has been a leader in the gay-rights movement here since the days when voters passed the state's antidiscrimination amendment in 1992. The bill's signing was especially poignant for Steadman, whose longtime partner, Dave Misner, died of cancer last year. They had been together for 11 years, a detail he included in the bill. The measure was Senate Bill 11.