On March 26 the Supreme Court will hear oral argument in Hollingsworth v. Perry, the legal challenge to California's Proposition 8, the 2008 voter initiative that amended the state constitution in order to forbid gay marriage. Leading the challenge against Prop. 8 are two of the country's most powerful lawyers, Theodore Olson, former solicitor general under President George W. Bush, and David Boies, former chief counsel of the Senate Judiciary Committee and former lead counsel for Vice President Al Gore in the 2000 case of Bush v. Gore (where Boies squared off against Olson before the Supreme Court).

Yesterday, Olson and Boies submitted their main brief in the case to the Supreme Court, and, in the words of SCOTUSblog's Lyle Denniston, it's nothing short of an "all-out assault" on the notion that banning gay marriage is consistent with the constitutional principles of liberty and equality.

It's a sweeping document. In its 54 pages, the brief repeatedly cites the Supreme Court's most significant civil rights decisions, from Brown v. Board of Education (1954), which nullified the doctrine of separate but equal, to Loving v. Virginia (1967), which struck down a state ban on interracial marriage. But it is the Supreme Court's 2003 ruling in Lawrence v. Texas that exerts perhaps the greatest influence over the case against Prop. 8. Not only is Lawrence cited more than a dozen times in the brief, but that ruling's central theme—liberty vs. state power—runs consistently throughout the Olson-Boies argument.

It's a bold strategy, but it may pay off. Justice Anthony Kennedy, the likely swing vote in the Prop. 8 case, also wrote the majority opinion in Lawrence, and as the libertarian legal scholar Randy Barnett has noted, Kennedy's Lawrence decision struck down Texas' ban on homosexual conduct not as a matter of "gay rights," but as a matter of liberty. Kennedy's ruling, Barnett observed, "requires the government to justify its restriction on liberty, instead of requiring the citizen to establish that the liberty being exercised is somehow 'fundamental.' In this way, once an action is deemed to be a proper exercise of liberty (as opposed to license), the burden shifts to the government." Texas, of course, could offer no legitimate reason to ban private homosexual conduct, therefore the Homosexual Conduct Law had to fall.

The Olson-Boies brief makes a similar claim about California's ban on gay marriage, arguing that the burden of proof should be on the government, and that Prop. 8's defenders have offered no rational justification for the restriction on liberty, and have instead endorsed "a cramped definition of marriage as a utilitarian incentive devised by and put into service by the State—society's way of channeling heterosexual potential parents into 'responsible pro-creation.'" Indeed, the brief argues, this "state-centric construct of marriage means that the State could constitutionally deny any infertile couple the right to marry, and could prohibit marriage altogether if it chose to pursue a society less committed to 'responsible' procreation."

Will this emphasis on liberty over state power prove successful? In his dissenting opinion in Lawrence, Justice Antonin Scalia attacked Kennedy for crafting a ruling that "dismantles the structure of constitutional law that has permitted a distinction to be made between heterosexual and homosexual unions, insofar as formal recognition in marriage is concerned." We'll soon find out whether Scalia was right to worry.