The Massachusetts attorney general, Martha Coakley, requested that a federal court in Boston yesterday strike down the federal ban on gay marriage, arguing that it interfered with the rights of individual states to define marriage and have those unions recognised by the federal government.

The Assistant Attorney General, Maura Healey, pointed out that historically, states have had the right to define marriage on their own terms and that the 1996 Defense of Marriage Act (DOMA) could result in the denial of Medicaid and other benefits to same-sex married couples in the state.

However, Christopher Hall, a lawyer for the US Justice Department, said that the federal government was well within its rights to set eligibility requirements for federal benefits and that his included the law that such benefits would only go to opposite-sex married couples.

DOMA has been challenged twice in a federal court this month. A coalition of gay rights groups brought their cause before the same judge earlier in May, arguing that it was unconstitutional to deny federal benefits to gay couples when they were available to straight couples.

In her argument, Ms Healey spoke about a military veteran’s request that when he and his same-sex spouse die, they be buried together in a veterans’ cemetary – the right of every straight military couple. She said the state had decided to authorise the burial because “it was the right thing to do” despite the potential loss of federal money for the action.

Ms Healy also argued that not only did the law tresspass on an area of core state sovereignty, but that it “forces Massachusettes to discriminate against its own citizens.”

The state has allowed over 15,000 same-sex couples to marry since 2004.