The Wisconsin Supreme Court will now decide whether the state's domestic partnership registry is legal under the state constitution.
Members of the conservative group Wisconsin Family Action filed a lawsuit in 2010 alleging the registry violates a 2006 state constitutional amendment banning gay marriage or anything substantially similar. The registry grants same-sex couples a host of legal rights.
"This case is not about benefits," Austin Nimocks, an attorney for the group, said Wednesday. "This case is rather about Chapter 770 mimicking marriage's blueprint in the Wisconsin code."
Christopher Clark, an attorney for Fair Wisconsin, the state's largest gay rights group, said the registry doesn't come close to marriage.
"The purpose of the legislation was to provide limited legal protections to gay couples and do it in accordance with the amendment passed in 2006," said Clark.
The gay couples represented by Fair Wisconsin watched the arguments in court.
"I was emotional during the testimony," said Kathy Flores, of Appleton. "We're talking about a law, I understand. But this is our lives."
The president of the group that brought the suit said she believes the justices will side with them.
"I'm going to say I'm cautiously optimistic that the rule of law will prevail and we will get a decision that will not be judicially activist in nature," said Julaine Appling, with Wisconsin Family Action.
The justices will now deliberate on the issue and write briefs with their decision. There's no timeline on how soon that may happen.