When the Constitution requires a state court to apply sister state law to a case before it, how faithfully must the state court interpret that law? By declining to review a state high court’s apparent misconstruction of sister state law, the Supreme Court has given state courts nearly unlimited freedom to construe sister state laws however they wish to. As a consequence, the constitutional constraints on choice of law mean little: a state court compelled to apply sister state law can simply interpret that law to match its own state’s law.
This Note argues that the Supreme Court should not be so deferential to state court misconstructions of sister state law when application of that law is required by the Constitution. Three changes in the legal landscape since the Court first held it had no power to review such misconstructions support this conclusion: first, the Court no longer exercises mandatory review via the writ of error; second, courts now treat issues of sister state law as issues of law, not issues of fact; and third, the Court now recognizes a constitutional right to the application of sister state law in certain circumstances. When state high courts misconstrue state laws in ways that threaten other constitutionally-protected rights, such as those protected by the Contracts Clause and the Due Process Clause, the Supreme Court has long held that it can review those misconstructions. The same should be true for misconstructions that undermine the constitutional constraints on choice of law.