(CNN) -- The legalization of same-sex marriage has given way to a new problem for a Pennsylvania couple, who technically are father and son.
Before states across the country began striking down bans on same-sex marriage and the Supreme Court ultimately decided the issue nationwide, some gay couples used adoption laws as a way to gain legal recognition as a family, and the related benefits such as inheritance and hospital visitation rights.
Nino Esposito, a retired teacher, adopted his partner Roland "Drew" Bosee, a former freelance and technical writer, in 2012, after more than 40 years of being a couple.
Now, they're trying to undo the adoption to get married and a state trial court judge has rejected their request, saying his ability to annul adoptions is generally limited to instances of fraud.
"We never thought we'd see the day" that same-sex marriage would be legal in Pennsylvania, Esposito, 78, told CNN in a telephone interview.
The adoption "gave us the most legitimate thing available to us" at the time, said Bosee, 68.
The adoption process Bosee and Esposito went through was not uncommon. Although it is difficult to gather hard numbers, the ACLU of Pennsylvania, a group supporting the couple, says it learned that many couples in states across the country lawfully took advantage of adoption laws in order to protect their relationships. Now these couples seek to marry, but first they must confront state adoption laws that provide no easy path to annulment.
In Pennsylvania, Esposito and Bosee knew other couples who successfully annulled their adoptions in order to marry.
They quickly made plans to do the same after Pennsylvania legalized marriage between same-sex couples in May 2014.
"We realized we could have a complete union, which is what we want," Esposito said.
But Judge Lawrence J. O'Toole, of the Court of Common Pleas of Allegheny County, ruled against the couple. He noted that the primary purpose of the adoption was to reduce the Pennsylvania inheritance tax payable upon the death of one of the men from 15% to 4%, "as the two men would now be in a parent-child relationship instead of a third party relationship."
O'Toole said he was "sensitive to the situation" but noted that despite the fact Esposito and Bosee desire to marry, "they cannot do so because they are legally father and son."
"This Court welcomes direction from our appellate courts in handling parallel cases," O'Toole wrote.
"We don't believe the Pennsylvania judge who refused to annul this adoption was unsympathetic," said Witold Walczak, the Legal Director of the ACLU Pennsylvania, "he simply felt that the legal path to doing so should be forged by an appellate court."
"The ACLU is hopeful that the Superior Court will apply established legal principles to allow annulment of adoptions by same-sex couples who that they can finally partake of their constitutional right to marry," Walczak said.
While in most of the country there have not been problems implementing the U.S. Supreme Court's decision in Obergefell vs. Hodges, there have been some pockets of resistance.
Some probate judges and other public officials in the South, citing religious objections, stopped issuing marriage licenses all together to avoid issuing licenses to gay couples.
Pennsylvania Democratic Sen. Bob Casey, in a letter Monday to Attorney General Loretta Lynch, asked that the Justice Department weigh in on the side of Esposito and Bosee.
"LGBT couples should have the right to obtain a marriage license, no matter the state or jurisdiction in which they reside," Casey wrote. "In adoption cases such as these, the law has changed dramatically since the adoptions were first carried out."
Attorneys Mikhail Pappas and Andrew Gross, who represent Esposito and Bosee, say they would welcome help from the Justice Department to make clear their clients have a civil right at issue in the case.
In court papers, the attorneys argued: "The personal and social benefits of marriage are legion and unparalleled relative to any other association between individuals that our society formally sanctions and recognizes."
Dena Iverson, a Justice Department spokeswoman, said the department received Casey's letter and is reviewing his request.
Esposito and Bosee said they're being cautious now about planning a wedding. When they filed their adoption annulment they anticipated being able to marry the same day.
"We had our $80 in cash and we were ready to go across the street to get our license. Judge O'Toole had other ideas," Esposito said.
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