Crabtree was openly skeptical of the state's arguments that the 2006 voter-approved ban protects the procreative nature of marriage. He mentioned two of his friends who are marrying this summer at age 65.
"Their marriage is not about having any more kids," he quipped.
Crabtree heard arguments in lawsuits filed by one couple in Adams County and eight in Denver who are seeking to be recognized as married couples in Colorado. He said he would issue a written decision rather than rule from the bench and noted that his decision will likely be appealed all the way to the Colorado Supreme Court.
Several of the rulings striking down same-sex marriage bans in other states have been put on hold, Crabtree said, suggesting the judge might prevent any ruling from going into effect until appeals are exhausted.
Attorney General John Suthers' office defied calls by some activists to follow the examples of attorneys general in seven other states who have declined to defend their state prohibitions.
Assistant Solicitor General Michael Francisco warned the judge that no one knows what the true impact could be of overturning the Colorado's ban.
"It will have real-world consequences," Francisco said, comparing it to state laws passed 40 years ago making divorce easier.
Gov. John Hickenlooper's office did not take a side in the case. The governor's chief lawyer, Jack Finlaw, said in court that the governor upholds the law but opposed the ban when it was on the ballot in 2006. He urged a ruling "respectful of the rights of all Coloradans."
Ralph Ogden, an attorney representing one of the couples, said the ban "has created two classes of citizens: One can be married, the other cannot."
But Francisco said Colorado voters have the ability to make that distinction. He told Crabtree that the judges who have struck down gay marriage bans elsewhere are guessing that the U.S. Supreme Court will declare gay marriage a constitutional right, but it is not the job of lower court judges to predict such a ruling.
"This court must draw its own conclusion," he said.
Crabtree was incredulous. "What am I supposed to do?" he asked. "Just punt?"