The United States Supreme Court is likely to strike down the Defense of Marriage Act (DOMA) as unconstitutional, with an 80 percent probability according to analysts writing for SCOTUSblog.

Five justices–Elena Kagan, Sonia Sotomayor, Stephen Breyer, Ruth Bader Ginsburg and Anthony Kennedy–are likely to strike down the policy, although for different reasons. Four justices may decide DOMA violates the equal protection clause under the Fifth Amendment, while Kennedy may strike it down as violating states’ rights.

The lawsuit, United States v. Windsor began in 2011 when Edith Windsor, an 83-yr-old New York woman, challenged DOMA, an act passed by congress in 1996. The law defines marriage as being between a man and one woman. Windsor was left with an estate tax bill of about $360,000 when her wife died in 2009 because they were not recognized by the federal government as a married couple.

Like Hollingsworth v. Perry, the questions before the court were about the legal standing of DOMA’s defense team, the validity of the court to hear the case in the first place and the question of whether or not DOMA violates the constitutional promise of equal protection under the law.

According to SCOTUS blogger, Amy Howe, unlike in Tuesday’s hearing, it did not seem that at least five justices seriously doubted whether or not DOMA’s defense team, the Bipartisan Legal Advisory Group (BLAG), could come to DOMA’s defense.

The standing question was brought up due to unprecedented events that complicates the usual legal procedure.

As in Hollingsworth, the United States government did not come to DOMA’s defense when Windsor filed her suit in a lower court because they deemed the policy to be unconstitutional. BLAG intervened to defend DOMA and when a lower court ruled that the policy was unconstitutional, it appealed to a higher court on behalf of the United States.

The judges have been cautious about how they will rule both the Proposition 8 case and the DOMA challenge, according to analysts. The relationship between the two cases is in itself problematic for both gay rights advocates and marriage traditionalists.

“Students of Windsor and Hollingsworth have always recognized a basic tension between the theories of gay-rights advocates in the cases,” wrote SCOTUS blogger Tom Goldstein. “The challenge to DOMA is undergirded by a sense that marriage is a matter for state rather than federal regulation. The challenge to Proposition 8 is a direct challenge to just such a decision by a state.”

Supreme Court hears DOMA arguments

The day after hearing arguments for Prop 8 in Hollingsworth v. Perry, the Supreme Court takes up United States v. Windsor, a case challenging the 1996 Defense of Marriage Act. News orgs, politicians, celebrities and others share on social media about the DOMA case.

Storified by Daily Sundial· Wed, Mar 27 2013 19:52:44