The commonwealth filed a similar petition Monday, said Joshua Maus, a spokesman for the Office of General Counsel.
The ACLU and others filed suit last July on behalf of 11 couples and a widow who said the ban violates the state constitution by excluding same-sex couples from the same legal benefits and protections as heterosexual couples.
The deadline for legal papers to be filed in the case is May 12, which means a ruling could come at any time after that date, the plaintiffs' attorneys said.
"We put forth the most extensive grouping of experts of any similar case around the country because we think this is one of the most definitive cases in the country," said Mark Aronchick, a partner with the Philadelphia firm Hangley Aronchick, which also is representing the plaintiffs. "We wanted through this case to answer all of the questions that have ever been raised related to freedom to marry."
Since the suit was filed, courts at the state and federal levels in 12 states have found in favor of same-sex marriage, either by overturning same-sex marriage bans - such as a judge did in New Jersey - or allowing the recognition of marriages in other states.
The case before Jones, Whitewood v. Wolf, is one of seven same-sex marriage cases under consideration by courts in Pennsylvania. Oral arguments are scheduled for May 15 in Palladino v. Corbett and Kane before U.S. District Court in Philadelphia.
An appeal of a Commonwealth Court ruling by Montgomery County Register of Wills L. Bruce Hanes over his issuance of marriage licenses to same-sex couples is pending in the Pennsylvania Supreme Court.