Akil Amar’s new book discusses many different components of
the “unwritten” constitution. This Article looks specifically at the
most common use of that term—the practice of striking down state
and federal laws on the grounds that they violate “fundamental
rights” not directly mentioned in the Constitution. Although the
Court’s favored approach to finding unenumerated rights—so-called
“substantive due process”—is neither historically supportable nor ju-
risprudentially coherent, other sources of unenumerated rights are
more promising. The Ninth Amendment would support a jurispru-
dence of natural rights based on equitable interpretation, and the
Privileges or Immunities Clause might support a jurisprudence of
broadly accepted traditional rights.