( CNN ) The justices of the Supreme Court practice politics as much as law -- and that will be clearer than ever when the issue of same-sex marriage comes before the court on Tuesday . Public opinion on same-sex marriage has turned upside down since the Supreme Judicial Court in Massachusetts first legalized the practice in 2003 . Overwhelming opposition has turned into substantial majority support , especially among young people of all political persuasions . Even the name of the issue has changed -- to marriage equality . Of course , the Constitution has not changed since 2003 , a point that will surely be made by such opponents of same-sex marriage as Justice Antonin Scalia . To originalists like Scalia -- those who believe the Constitution should be interpreted only as it was originally understood by the framers -- the idea of a constitutional right to same-sex marriage is anathema . To them , the Constitution means only what it meant to those who wrote it -- and James Madison ( or the authors of the 14th Amendment , just after the Civil War ) never gave a thought to whether they were granting gay people the right to marry . But the Supreme Court has always been about a lot more than the intentions of the framers . And public opinion is just one of the extrajudicial factors that the justices sometimes take into consideration . In 1954 , the Supreme Court ruled unanimously that public schools could no longer segregate students by race , even though the authors of the 14th Amendment clearly considered segregated schools to be permissible . Chief Justice Earl Warren , who wrote the opinion in Brown v. Board of Education , recognized that the world had changed , especially in light of the Cold War . Warren knew that segregated schools damaged the United States ' reputation in the contest for hearts and minds around the world , and he steered the court accordingly . Warren 's motives had nothing to do with the framers ' intentions , and little to do with the words of the Constitution itself , but these kinds of motivations have been common throughout the history of the Supreme Court . There are risks , of course , when the justices are guided by more than the text and history of the Constitution . Like everyone else , the justices have imperfect instincts when it comes to measuring public attitudes . Justice Ruth Bader Ginsburg is a fervent supporter of abortion rights for women , but she has expressed reservations about the court 's decision in Roe v. Wade , the 1973 ruling that required all 50 states to legalize abortion . She has argued that the court interrupted a political process for legalization that was already underway , and that the case ignited a backlash that wound up hurting the cause of abortion rights . Her position is debatable on several scores . Abortion rights were not ascendant everywhere in the '70s , and opponents were already well mobilized . But Ginsburg 's misgivings about Roe have served as an important backdrop to the Supreme Court 's consideration of same-sex marriage . Still , when it comes to Supreme Court decisions , it is usually safe to bet that a majority of the justices will come down on the side favored by most of the public . In any case , as we head into the argument , it looks like most of the justices have already made up their minds . After the court decided United States v. Windsor in 2013 , which invalidated most of the 1996 law known as the Defense of Marriage Act , more than a dozen federal district courts around the county said the reasoning of that case required the legalization of same-sex marriage . These judges allowed these marriages to begin taking place around the country . Supporters of the existing laws went to the Supreme Court and asked for stays of the lower court rulings , because the justices themselves had not yet permitted the marriages to take place . But in each case , the Supreme Court denied the stays and allowed same-sex marriages to proceed -- those marriages are now legal in 37 states and the District of Columbia . In a brief dissenting opinion from the failure to grant the stays , Justice Clarence Thomas suggested the issue had already been settled in the minds of his colleagues . `` This acquiescence [ in allowing marriages to proceed ] may well be seen as a signal of the court 's intended resolution of that question , '' Thomas wrote . `` This is not the proper way to discharge our ... responsibilities . '' But Thomas only drew Scalia to join his dissent , suggesting that even fellow conservatives Chief Justice John Roberts and Samuel Alito saw the writing on the wall . In any case , at oral argument , we 'll get a clue what the justices are thinking about the issue . But we already know that their decision , like so many in the court 's history , will be based on a great deal more than the text of the Constitution .
Jeffrey Toobin : refusing to recognize same - sex marriages as U.S. largely in principle . Did framers intend this ? That does n't always matter . He says opinions on the court may conform to conservative view , but most of the judges have given notice that they see writing on wall .