[JURIST] Attorneys for Edith Windsor [NYT profile], the respondent in US v. Windsor [docket], filed a brief [text, PDF] with the US Supreme Court [official website] on Tuesday arguing that the Defense of Marriage Act (DOMA) [text; JURIST news archive] is unconstitutional. Windsor, the surviving spouse of a same-sex couple, initiated the legal challenge to DOMA after she was denied the spousal deduction for federal estate taxes because Section 3 of DOMA defines “marriage” under federal law as a “legal union between one man and one woman as husband and wife” and “spouse” as a “person of the opposite sex who is a husband or wife.” Windsor’s brief argues that DOMA violates the Equal Protection Clause of the US Constitution because the law fails to satisfy a heightened scrutiny [Cornell LII backgrounder] in that it “cannot be justified as substantially furthering any important governmental interest.”

Tuesday’s brief adds to the three that were filed [JURIST report] last week, including one filed by the Obama administration arguing that DOMA is unconstitutional and one filed by the Bipartisan Legal Advisory Group (DOMA) defending the law’s constitutionality. After the Obama administration announced [JURIST report] in 2011 that it would no longer defend DOMA’s constitutionality in court, Republicans in the US House of Representatives formed [JURIST report] the BLAG to take up the mantle of defending the law. DOMA was struck down [JURIST report] by the US District Court for the Southern District of New York and the US Court of Appeals for the Second Circuit [official websites], prompting the petition [text, PDF] to the US Supreme Court. This term, the US Supreme Court will also be ruling on the constitutionality of California’s Proposition 8 [JURIST news archive], which banned same-sex marriage [JURIST backgrounder] throughout the state.