The Constitution contains two clauses that protect persons against governmental interference with their property. The Due Process Clause provides that "No person shall ... be deprived of life, liberty, or property, without due process of law." The Takings Clause adds, "nor shall private property be taken for public use, without just compensation." Both provisions appear to impose a threshold condition that a claimant have some "property" at stake before the protections associated with the Clause apply. Thus, under the Due Process Clause, it would seem that a claimant must have an interest in "property" (or in "life" or "liberty") before we move on to ask whether the state has "deprived" such a person of this interest without "due process of law." And the Takings Clause appears to require that a claimant have "private property" before we proceed to ask whether this interest has been "taken" by the government for a "public use" without the payment of "just compensation."
The Supreme Court has not always been attentive to the "property" threshold under these clauses. During a brief period in the early 1970s, it spoke as if procedural due process applies to any interest that is "important," whether or not such an interest can be properly categorized as "property" (or "life" or "liberty"). In addition, cases from the 1960s and early 1970s seem to say that the substantive due process requirement of minimum rationality applies even if a claimant has no liberty or property interest.
Thomas W. Merrill,
The Landscape of Constitutional Property,
Va. L. Rev.
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