Gay and lesbian service members and veterans plan to file suit Thursday challenging the constitutionality of the federal ban on gay marriage and federal policy that define a spouse as a person of the opposite sex.

The suit comes five weeks after the Pentagon ended its ban on gays in the military.

Lawyers plan to sue in federal district court in Boston, the same court that ruled last year that the federal Defense of Marriage Act is unconstitutional because it interferes with a state’s right to define marriage. That decision is being appealed in the U.S. Court of Appeals for the 1st Circuit.

The 1996 law bars federal recognition of same-sex marriages performed in states that allow them.

The suit also challenges provisions of federal code regarding spouses that lawyers said bar gay couples from accessing benefits provided by the Pentagon and the Department of Veterans Affairs. Those benefits include military identification cards, access to bases, recreational programs, spousal support groups and burial rights at national cemeteries.

Casey and Shannon McLaughlin, pictured with their twins, Grace, left, and Grant, right, plan to file suit in federal court challenging the constitutionality of the Defense of Marriage Act. (Casey and Shannon McLaughlin)

Massachusetts Army National Guard Maj. Shannon McLaughlin, 41, and her wife, Casey, 34, are serving as lead plaintiffs in the suit, which includes five other troops and two career Army and Navy veterans.

The McLaughlins, from Foxboro, Mass., married in December 2009 and have 10-month old twins. Massachusetts legalized same-sex marriage in 2004.

Although Shannon pays for the twins’ health care through her military benefits, Casey, a former high school history teacher who gave birth to the twins, pays about $700 a month for a separate health-care account, the couple said.

“What Shannon and Casey are seeking is the same treatment that their straight counterparts, who are legally married, receive every day without question and take for granted,” said Aubrey Sarvis, executive director of the Servicemembers Legal Defense Network, which helped organize the suit and once represented troops discharged for violating “don’t ask, don’t tell.”

Since the ban on gays ended, Shannon said that she and her wife no longer face the anxiety that she might lose her job because she’s gay.

But Casey said they now face “a different anxiety” that involves juggling different health-care accounts and preparing for Shannon’s possible overseas deployment.

If Shannon is deployed, Casey would be barred from taking the twins to regular medical appointments at a nearby military base, the couple said.

Sarvis said that several potential plaintiffs backed out of the suit for fear of retribution from military commanders.

“It’s a big deal to sue any employer, but when in the military — when you hope to make a 20- or 30-year career — or you hope to make the next promotion, you think two or three times before doing this,” Sarvis said.

Dozens of legal challenges to DOMA are making their way through federal courts, but gay rights’ legal advocates have said they do not anticipate a Supreme Court decision on the issue until 2013.

After couples in states that recognize gay marriage began suing, the Obama administration decided this year that it would no longer defend the law. In response, House Republicans tapped former solicitor general Paul D. Clement to defend the law. The office of House Speaker John A. Boehner (R-Ohio), who hired Clement, referred questions Wednesday to Clement’s office; he did not respond to reporter inquiries.

Pentagon spokeswoman Eileen Lainez said Wednesday that officials were “engaged in a careful and deliberate review” of whether some benefits can be extended to same-sex partners.

Veterans Affairs spokesman Josh Taylor said that department lawyers plan to review the case once it is filed.


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