A gay couple in the US say they have had to use adoption to lessen the inheritance tax they will have to pay due to their state’s lack of same-sex marriage laws.

ABC reports that the couple, who go by the names John and Gregory, met nearly 45 years ago in a gay bar in Pittsburgh, Pennsylvania.

Having lived through years of enormous progress in gay rights, the two men are still unable to get married in their home state.

Instead, 65-year-old John has adopted 73-year-old Gregory. Although John is the younger of the two, his father is still alive, so he could not become the adoptee.

“If we just live together and Gregory willed me his assets and property and anything else, I would be liable for a 15 percent tax on the value of the estate,” said John. “By adoption, that decreases to 4 percent. It’s a huge difference.”

“I had panic attacks about a sibling swooping down if Gregory predeceased me,” he said. “A couple of siblings are homophobic and I thought, we better get our ducks in a row.”

Gay and Lesbian Advocates and Defenders (GLAD) lawyer Jason Wu said he had seen several cases similar to that of John and Gregory in the past.

However, he felt their case stood out as an example of how much progress is still needed in the US, where the Supreme Court overturned the Defense of Marriage Act this week.

“As tremendous as the victory was at the Supreme Court, it was a victory half-finished,” he said.

“There are still over 30 states where couples are denied the ability to protect their families,” he added. “What you see with [John and Gregory], unfortunately, is what so many couples are still being forced to do. They think of creative ways to ensure protection for each other to make medical decisions and inherit property after one has passed away.”

Cases of same-sex couples adopting one another to avoid taxes make an ironic contrast to claims that marriage equality would lead to same-sex family members marrying one another for the same reason.

Among others, Lord Norman Tebbit claimed that same-sex siblings and parents would marry each other in order to claim financial benefits.

“Why shouldn’t a mother marry her daughter? Why shouldn’t two elderly sisters living together marry each other? I quite fancy my brother!” he said.