While more than 70 percent of U.S. states now allow same-sex marriage, the waves of change have yet to reach America's far-flung and socially conservative territories in the Caribbean and Pacific.
Of the five territories, only Puerto Rico has faced a lawsuit seeking the right for gay and lesbian couples to wed, and a federal judge there - bucking the trend in federal courts on the mainland - rejected the suit. That case is under appeal before the 1st U.S. Circuit Court of Appeals in Boston.
In the other four territories - the U.S. Virgin Islands, Guam, American Samoa and the Northern Marianas - no gay or lesbian couples have stepped forward to make a legal case for marriage rights, according to advocacy groups monitoring the situation.
The five territories would be covered by a possible U.S. Supreme Court ruling establishing a constitutional right for same-sex couples to wed, notes Omar Gonzalez-Pagan, an attorney with the national gay-right s group Lambda Legal. Several same-sex marriage cases from the mainland are before the high court this spring, and a ruling is expected by the end of June.
Gonzalez-Pagan said he hoped same-sex couples in the territories would step forward to seek marriage rights.
"No matter how big or small the population might be in any one of these territories, or the fact there's vehement opposition in them, it doesn't mean any citizens should be left behind," he said. "All of them have a fundamental right to marry. They're all entitled to equal protection."
The only pending territorial lawsuit involving gay marriage was filed in Puerto Rico last year by five couples - two who are seeking to marry in Puerto Rico and three who live on the island and want recognition of marriages that occurred elsewhere.
In October, U.S. District Court Judge Juan Perez-Gimenez upheld Puerto Rico's ban on same-sex marriage, saying voters and legislators, not judges, should decide the issue.
On the mainland, four U.S. circuit courts of appeal have ruled in favor of same-sex marriage, while one - the 6th Circuit - upheld the laws in four states that prohibit it.
Lambda Legal is now appealing Perez-Gimenez' ruling before the 1st Circuit; no date for oral arguments has been set.
Among the plaintiffs are Johanne Velez Garcia and Faviola Melendez Rodríguez, who have been a couple for six years and married in New York in 2012. They have been trying to adopt a child for several years, and believe their efforts have been thwarted because Puerto Rico does not recognize their marriage.
Velez, a 50-year-old attorney and consultant, said she's optimistic that the Supreme Court will rule in favor of same-sex marriage and thus nullify Puerto Rico's ban. Meanwhile, she has been heartened by the support of family and friends as the lawsuit proceeds.
"When the news came out that we were filing this case, Faviola and I were a little apprehensive," Velez said.
"But what we received were positive comments, expressions of love and support even from acquaintances who, due to religious reasons, might not be too happy about what we were doing," she added. "Even those people understand we are fighting for our rights."
However, the leader of the conservative group Puerto Rico for Families, pastor and physician Cesar Vazquez, says he and his allies will be dismayed if the Supreme Court decides to legalize same-sex marriage.
"It doesn't mean we have to approve of it, and it doesn't mean we can't keep educating people," said Vazquez, who expressed concern that schools might be required to teach children that same-sex marriage is "a valid alternative."
In the other Caribbean territory - the U.S. Virgin Islands - there is strong opposition to same-sex marriage from leaders of various Christian denominations. A member of the territory's Senate riled some of those leaders last year by drafting a bill that would have legalized gay marriage, but the bill has not advanced.
In the western Pacific territory of Guam, where more than 80 percent of the residents are Roman Catholic, the church helped defeat a bill to recognize same-sex unions in 2009. It was introduced by the vice speaker of the territorial legislature, Sen. Benjamin Cruz, who is openly gay.
Cruz said he tried to find gay couples willing to campaign publicly for same-sex marriage, but only one couple stepped forward, and he's now ceased his advocacy efforts.
"Why should I be the only one that gets the nasty stares in church?" he asked.
Several gay couples have gone off-island to marry, but their unions are not recognized when they return to Guam even though they enjoy federal benefits, such as filing joint tax returns.
Joseph Querimit, 32, and Simon-Joseph Querimit, 31, flew to Hawaii to marry in April 2014; they are now raising an 8-year-old child.
Joseph said he would have preferre d to marry on Guam, "but I didn't want to face all the ridicule."
"Born and raised on Guam, being Catholics, the upbringing, it's just not something you would go out there and flaunt," he said.
A lesbian couple - Dausha Magalhaes, 30, and her wife, Richelle, 32 - have lived on Guam since April 2013, shortly after they were married in Massachusetts, and find the island more welcoming than parts of Texas where they once resided.
"We don't have to be scared if we want to hold hands," Dausha said. "We do not get stared at or gawked at, and I have not once felt like a social pariah like I do back home."
The other two Pacific territories - American Samoa and the Northern Marianas - do not recognize same-sex marriages even though they have no formal ban. American Samoa's Office of Vital Statistics said it has not received any request from same-sex couples seeking a marriage license, and local lawyers have not taken up the cause.
Galeai Tu'ufuli, one of American Samoa's paramount traditional chiefs and a member of territorial Senate, said he is neither for nor against gay marriage, but cited prevailing religious views that a marriage should be between a man and a woman.
"Why test the waters now by introducing legislation to deal with this issue?" said Tu'ufuli. "Time will tell when and if this issue surfaces in the future."
Christian churches with conservative social views predominate in American Samoa, and the government's motto is, "Samoa, Let God Be First." Yet the territory also has a tradition of embracing its community of fa'afafine - males who are raised as females and adapt feminine traits.
Many of the fa'afafine are college-educated and hold professional jobs. Some older members of the community have cautioned against joining in same-sex marriage advocacy for fear of roiling the status quo, while some younger members have chosen differently.
"I joined the minority in pushing for same-sex marriage and for equal rights for happiness," said 29-year-old Princess Auva'a, a well-known fa'afafine.
Together, the five U.S. territories have almost 4 million residents - more than 3.5 million of them in Puerto Rico. As of the 2010 U.S. census, Guam had 159,358 residents, the U.S. Virgin Islands 106,405, American Samoa 55,519 and the Northern Marianas 53,883.
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